Optimization of Southeastern Forest Biomass Crop Production: A Watershed Scale Evaluation of the Sustainability and Productivity of Dedicated Energy Crop and Woody Biomass Operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chescheir, George M.; Nettles, Jami E,; Youssef, Mohamed

Growing switchgrass (Panicum virgatum L.) as an intercrop in managed loblolly pine (Pinus taeda L.) plantations has emerged as a potential source of bioenergy feedstock. Utilizing land resources between pine trees to produce an energy crop can potentially reduce the demand for land resources used to produce food; however, converting conventionally managed forest land to this new intercropping system constitutes changes in land use and associated management practices, which may affect the environmental and economic sustainability of the land. The overall objective of this project is to evaluate the environmental effects of large-scale forest bioenergy crop production and utilize thesemore » results to optimize cropping systems in a manner that protects the important ecosystem services provided by forests while contributing to the development of a sustainable and economically-viable biomass industry in the southeastern United States. Specific objectives are to: Quantify the hydrology of different energy crop production systems in watershed scale experiments on different landscapes in the southeast. Quantify the nutrient dynamics of energy crop production systems in watershed scale experiments to determine the impact of these systems on water quality. Evaluate the impacts of energy crop production on soil structure, fertility, and organic matter. Evaluate the response of flora and fauna populations and habitat quality to energy crop production systems. Develop watershed and regional scale models to evaluate the environmental sustainability and productivity of energy crop and woody biomass operations. Quantify the production systems in terms of bioenergy crop yield versus the energy and economic costs of production. Develop and evaluate best management practice guidelines to ensure the environmental sustainability of energy crop production systems. Watershed and plot scale studies formed the core of this research platform. Matched-watershed studies were established in North Carolina, Mississippi and Alabama. A plot scale study was also established in North Carolina to more intensive examination of the effects of biomass production on hydrology, soil properties, productivity wildlife habitat, and biodiversity on replicate 0.8 ha plots. Studies were also conducted on selected sites to define and quantify the environmental effects of biomass production on wildlife habitat, biodiversity, soil properties and productivity, and carbon storage and flux. Treatments on the sub-watersheds and plots included potential operational systems ranging from monoculture switchgrass to interplanted switchgrass to conventional managed forests as a controls. The hydrology, water quality, soil property, and productivity data collected in the watershed and plot scale experiments were used to develop process based watershed scale models. Existing models (DRAINMOD and APEX) were modified to more effectively simulate the intercropped systems. More regional scale models (DRAINMOD-INTERCROP) with GIS interface and SWAT) were used to simulate the impacts of intercropping switchgrass in pine plantations on the hydrology and water quality of larger scale watersheds. Results from the watershed and plot scale studies, and the modeling studies were used to develop Best Management Practice (BMP) guidelines to ensure environmentally sustainable bioenergy production in the forestry setting. While the results of the environmental sustainability research for this project have become publically available, many of the planning decisions and operational trial results were not public. Personnel in management, planning, operations, and logistics were interviewed to capture the important economic and operational lessons from internal operational research on approximately 30 full-scale operational tracts. This project produced a very large database documenting the impact of interplanting switchgrass with pine trees on hydrology, water quality, soil quality, and biodiversity. Some environmental impacts were observed in response to additional operations required for interplanting, but these impacts were small and short lived. Given that existing forestry BMPs provide a flexible system that can be adapted to protect water quality and biodiversity in forestry settings, interplanting switchgrass with pine trees can be considered environmentally sustainable. The project also developed models that can simulate switchgrass growth when it is in competition with pine trees as well as the hydrology and nutrient dynamics that result from this interplanted system. The models predicted switchgrass production, water use, and the quality of the water leaving the system over a range of climatological and geographic conditions. These models can be used to guide decisions toward sustainability. The project also documented the limitations of switchgrass production in the forestry setting and the challenges and increased costs arising from this practice. These challenges led to the conclusion that intercropping switchgrass with pine trees is not economically feasible in the current economic climate. Despite the barriers obstructing use of this system at this point in time, economic and technological changes may occur that will make this a feasible system for bioenergy production in the future. The data, models, BMPs and experiences documented in this report and in publications resulting from this project will be highly valuable to those implementing this system.« less

Intercropping Enhances Productivity and Maintains the Most Soil Fertility Properties Relative to Sole Cropping

PubMed Central

Wang, Zhi-Gang; Jin, Xin; Bao, Xing-Guo; Li, Xiao-Fei; Zhao, Jian-Hua; Sun, Jian-Hao; Christie, Peter; Li, Long

2014-01-01

Yield and nutrient acquisition advantages are frequently found in intercropping systems. However, there are few published reports on soil fertility in intercropping relative to monocultures. A field experiment was therefore established in 2009 in Gansu province, northwest China. The treatments comprised maize/faba bean, maize/soybean, maize/chickpea and maize/turnip intercropping, and their correspoding monocropping. In 2011 (the 3rd year) and 2012 (the 4th year) the yields and some soil chemical properties and enzyme activities were examined after all crop species were harvested or at later growth stages. Both grain yields and nutrient acquisition were significantly greater in all four intercropping systems than corresponding monocropping over two years. Generally, soil organic matter (OM) did not differ significantly from monocropping but did increase in maize/chickpea in 2012 and maize/turnip in both years. Soil total N (TN) did not differ between intercropping and monocropping in either year with the sole exception of maize/faba bean intercropping receiving 80 kg P ha−1 in 2011. Intercropping significantly reduced soil Olsen-P only in 2012, soil exchangeable K in both years, soil cation exchangeable capacity (CEC) in 2012, and soil pH in 2012. In the majority of cases soil enzyme activities did not differ across all the cropping systems at different P application rates compared to monocrops, with the exception of soil acid phosphatase activity which was higher in maize/legume intercropping than in the corresponding monocrops at 40 kg ha−1 P in 2011. P fertilization can alleviate the decline in soil Olsen-P and in soil CEC to some extent. In summary, intercropping enhanced productivity and maintained the majority of soil fertility properties for at least three to four years, especially at suitable P application rates. The results indicate that maize-based intercropping may be an efficient cropping system for sustainable agriculture with carefully managed fertilizer inputs. PMID:25486249

The behavior of Aphis gossypii and Aphis craccivora (Hemiptera: Aphididae) and of their predator Cycloneda sanguinea (Coleoptera: Coccinellidae) in cotton-cowpea intercropping systems.

PubMed

Fernandes, Francisco S; Godoy, Wesley A C; Ramalho, Francisco S; Malaquias, José B; Santos, Bárbara D B

2018-01-01

The intercropping is an important cultural practice commonly used in pest management. It is based on the principle that increased plant diversity in the agro-ecosystem can lead to reductions of pest populations in the crop. The current study aimed to assess the impact the colored fiber cotton-cowpea intercropped systems on Aphis gossypii and Aphis craccivora and on their predator Cycloneda sanguinea and the losses and the dispersion behavior of these aphids and their predator in these cropping systems. The experiment had a randomized block experimental design with two bioassays and four treatments. The number of apterous and alate aphids (A. gossypii) per cotton plant was 1.46 and 1.73 or 1.97 and 2.19 times highest in the solid cotton system than that found in the cotton-cowpea intercropped systems (S1) and (S2), respectively. On the other hand, the cotton-cowpea intercropped systems (S1 and S2) reduced, respectively, in 43% and 31% the number of apterousA. gossypiiper cotton plant compared to the control. Implementing cotton-cowpea intercropped system in the S1 scheme reduced A. gossypii infestation, favored the multiplication of C. sanguinea, and allowed obtaining heavier open bolls.

[Water-saving mechanisms of intercropping system in improving cropland water use efficiency].

PubMed

Zhang, Feng-Yun; Wu, Pu-Te; Zhao, Xi-Ning; Cheng, Xue-Feng

2012-05-01

Based on the multi-disciplinary researches, and in terms of the transformation efficiency of surface water to soil water, availability of cropland soil water, crop canopy structure, total irrigation volume needed on a given area, and crop yield, this paper discussed the water-saving mechanisms of intercropping system in improving cropland water use efficiency. Intercropping system could promote the full use of cropland water by plant roots, increase the water storage in root zone, reduce the inter-row evaporation and control excessive transpiration, and create a special microclimate advantageous to the plant growth and development. In addition, intercropping system could optimize source-sink relationship, provide a sound foundation for intensively utilizing resources temporally and spatially, and increase the crop yield per unit area greatly without increase of water consumption, so as to promote the crop water use efficiency effectively.

Intercropped Silviculture Systems, a Key to Achieving Soil Fungal Community Management in Eucalyptus Plantations

PubMed Central

Rachid, Caio T. C. C.; Balieiro, Fabiano C.; Fonseca, Eduardo S.; Peixoto, Raquel Silva; Chaer, Guilherme M.; Tiedje, James M.; Rosado, Alexandre S.

2015-01-01

Fungi are ubiquitous and important contributors to soil nutrient cycling, playing a vital role in C, N and P turnover, with many fungi having direct beneficial relationships with plants. However, the factors that modulate the soil fungal community are poorly understood. We studied the degree to which the composition of tree species affected the soil fungal community structure and diversity by pyrosequencing the 28S rRNA gene in soil DNA. We were also interested in whether intercropping (mixed plantation of two plant species) could be used to select fungal species. More than 50,000 high quality sequences were analyzed from three treatments: monoculture of Eucalyptus; monoculture of Acacia mangium; and a mixed plantation with both species sampled 2 and 3 years after planting. We found that the plant type had a major effect on the soil fungal community structure, with 75% of the sequences from the Eucalyptus soil belonging to Basidiomycota and 19% to Ascomycota, and the Acacia soil having a sequence distribution of 28% and 62%, respectively. The intercropping of Acacia mangium in a Eucalyptus plantation significantly increased the number of fungal genera and the diversity indices and introduced or increased the frequency of several genera that were not found in the monoculture cultivation samples. Our results suggest that management of soil fungi is possible by manipulating the composition of the plant community, and intercropped systems can be a means to achieve that. PMID:25706388

Intercropped silviculture systems, a key to achieving soil fungal community management in eucalyptus plantations.

PubMed

Rachid, Caio T C C; Balieiro, Fabiano C; Fonseca, Eduardo S; Peixoto, Raquel Silva; Chaer, Guilherme M; Tiedje, James M; Rosado, Alexandre S

2015-01-01

Fungi are ubiquitous and important contributors to soil nutrient cycling, playing a vital role in C, N and P turnover, with many fungi having direct beneficial relationships with plants. However, the factors that modulate the soil fungal community are poorly understood. We studied the degree to which the composition of tree species affected the soil fungal community structure and diversity by pyrosequencing the 28S rRNA gene in soil DNA. We were also interested in whether intercropping (mixed plantation of two plant species) could be used to select fungal species. More than 50,000 high quality sequences were analyzed from three treatments: monoculture of Eucalyptus; monoculture of Acacia mangium; and a mixed plantation with both species sampled 2 and 3 years after planting. We found that the plant type had a major effect on the soil fungal community structure, with 75% of the sequences from the Eucalyptus soil belonging to Basidiomycota and 19% to Ascomycota, and the Acacia soil having a sequence distribution of 28% and 62%, respectively. The intercropping of Acacia mangium in a Eucalyptus plantation significantly increased the number of fungal genera and the diversity indices and introduced or increased the frequency of several genera that were not found in the monoculture cultivation samples. Our results suggest that management of soil fungi is possible by manipulating the composition of the plant community, and intercropped systems can be a means to achieve that.

Intercropped silviculture systems, a key to achieving soil fungal community management in eucalyptus plantations

DOE PAGES

Caio T.C.C. Rachid; Balieiro, Fabiano C.; Fonseca, Eduardo S.; ...

2015-02-23

Fungi are ubiquitous and important contributors to soil nutrient cycling, playing a vital role in C, N and P turnover, with many fungi having direct beneficial relationships with plants. However, the factors that modulate the soil fungal community are poorly understood. We studied the degree to which the composition of tree species affected the soil fungal community structure and diversity by pyrosequencing the 28S rRNA gene in soil DNA. We were also interested in whether intercropping (mixed plantation of two plant species) could be used to select fungal species. More than 50,000 high quality sequences were analyzed from three treatments:more » monoculture of Eucalyptus; monoculture of Acacia mangium; and a mixed plantation with both species sampled 2 and 3 years after planting. We found that the plant type had a major effect on the soil fungal community structure, with 75% of the sequences from the Eucalyptus soil belonging to Basidiomycota and 19% to Ascomycota, and the Acacia soil having a sequence distribution of 28% and 62%, respectively. The intercropping of Acacia mangium in a Eucalyptus plantation significantly increased the number of fungal genera and the diversity indices and introduced or increased the frequency of several genera that were not found in the monoculture cultivation samples. Our results suggest that management of soil fungi is possible by manipulating the composition of the plant community, and intercropped systems can be a means to achieve that.« less

[Effects of nitrogen management on maize nitrogen utilization and residual nitrate nitrogen in soil under maize/soybean and maize/sweet potato relay strip intercropping systems].

PubMed

Wang, Xiao-Chun; Yang, Wen-Yu; Deng, Xiao-Yan; Zhang, Qun; Yong, Tai-Wen; Liu, Wei-Guo; Yang, Feng; Mao, Shu-Ming

2014-10-01

A large amount of nitrogen (N) fertilizers poured into the fields severely pollute the environment. Reasonable application of N fertilizer has always been the research hotpot. The effects of N management on maize N utilization and residual nitrate N in soil under maize/soybean and maize/ sweet potato relay strip intercropping systems were reported in a field experiment in southwest China. It was found that maize N accumulation, N harvest index, N absorption efficiency, N contribution proportion after the anthesis stage in maize/soybean relay strip intercropping were increased by 6.1%, 5.4%, 4.3%, and 15.1% than under maize/sweet potato with an increase of 22.6% for maize yield after sustainable growing of maize/soybean intercropping system. Nitrate N accumulation in the 0-60 cm soil layer was 12.9% higher under maize/soybean intercropping than under maize/sweet potato intercropping. However, nitrate N concentration in the 60-120 cm soil layer when intercropped with soybean decreased by 10.3% than when intercropped with sweet potato, indicating a decrease of N leaching loss. Increasing of N application rate enhanced N accumulation of maize and decreased N use efficiency and significantly increased nitrate concentration in the soil profile except in the 60-100 cm soil layer, where no significant difference was observed with nitrogen application rate at 0 to 270 kg · hm(-2). Further application of N fertilizer significantly enhanced nitrate leaching loss. Postponing N application increased nitrate accumulation in the 60-100 cm soil layer. The results suggested that N application rates and ratio of base to top dressing had different influences on maize N concentration and nitrate N between maize/soybean and maize/sweet potato intercropping. Maize N concentration in the late growing stage, N harvest index and N use efficiency under maize/soybean intercropping increased (with N application rate at 180-270 kg · hm(-2) and ratio of base to top dressing = 3:2:5) and decreased nitrate leaching loss with yield reaching 7757 kg · hm(-2) on average. However, for maize/sweet potato, N concentration and use efficiency and maize yield increased significantly with N application rate at 180 kg · hm(-2) and ratio of base to top dressing = 5:5 than that under other treatments with yield reaching 6572 kg · hm(-2). Under these circumstances, it would be possible to realize maize high yield, high efficiency and safety of N man- agement under maize/soybean and maize/sweet potato relay strip intercropping systems.

Breeding bird community response to establishing intercropped switchgrass in intensively-managed pine stands

USGS Publications Warehouse

Loman, Zachary G.; Riffell, Samuel K.; Wheat, Bradley R.; Miller, Darrin A.; Martin, James A.; Vilella, Francisco

2014-01-01

Intercropping switchgrass (Panicum virgatum L.) between tree rows within young pine (Pinus spp.) plantations is a potential method to generate lignocellulosic biofuel feedstocks within intensively managed forests. Intensively managed pine supports a diverse avian assemblage potentially affected by establishment and maintenance of an annual biomass feedstock via changes in plant communities, dead wood resources, and habitat structure. We sought to understand how establishing switchgrass on an operational scale affects bird communities within intercropped plantations as compared to typical intensively managed loblolly pine (Pinus taeda L.) forest. We conducted breeding bird point counts using distance sampling for three years (2011–2013) following establishment of intercropped switchgrass stands (6 replicates), traditionally-managed pine plantations, and switchgrass-only plots (0.1 km2 minimum) in Kemper Co., MS. We detected 59 breeding bird species from 11,195 detections. Neotropical migrants and forest-edge associated species were less abundant in intercropped plots than controls the first two years after establishment and more abundant in year three. Short distance migrants and residents were scarce in intercropped and control plots initially, and did not differ between these two treatments in any year. Species associated with pine-grass habitat structure were less abundant initially in intercropped plots, but converged with pine controls in subsequent years. Switchgrass monocultures provided minimal resources for birds. If songbird conservation is a management priority, managers should consider potential reductions of some breeding birds for one to two years following intercropping. It is unclear how these relationships may change outside the breeding season and as stands age.

Intercropped Pteris vittata L. and Morus alba L. presents a safe utilization mode for arsenic-contaminated soil.

PubMed

Wan, Xiaoming; Lei, Mei; Chen, Tongbin; Yang, Junxing

2017-02-01

Intercropping technology provides income for owners of contaminated soil without increasing environmental risk. Therefore, intercropping of arsenic (As) hyperaccumulator Pteris vittata L. with economic crops is now widely utilized in slightly or moderately As-contaminated farmlands. However, the mechanisms for As mobilization and absorption within the intercropping system are still unclear. To clarify As mobilization and absorption within an intercropping system, portable X-ray fluorescence spectrometry and sequential extraction were utilized to detect the spatial distribution and speciation of As in an intercropped system of P. vittata and cash crop mulberry (Morus alba L.). Compared with the P. vittata monoculture, P. vittata intercropping had higher As concentration, which may have been caused by the efficient exploitation of a greater As source in soil. Compared with the M. alba monoculture, M. alba intercropping had lower As concentration, which may have been caused by the As depletion by P. vittata roots. Spatial distribution of As in the soil indicated a "valley" around the P. vittata roots in both monocultured and intercropped systems, implying that As was depleted around the P. vittata roots. Continuous As extraction confirmed that both P. vittata monoculture and P. vittata and M. alba intercropping can efficiently control the risk of As soil contamination. Moreover, the properties of M. alba leaves were further studied. Mulberry leaves in the intercropping system satisfied the national feed standards. Therefore, intercropping presents a safe utilization mode for As-contaminated soil and can increase the income from silkworm-rearing M. alba leaves, without extra environmental risk. Copyright © 2016. Published by Elsevier B.V.

Intercropping for Management of Insect Pests of Castor, Ricinus communis, in the Semi—Arid Tropics of India

PubMed Central

Srinivasa Rao, M.; Venkateswarlu, B.

2012-01-01

Intercropping is one of the important cultural practices in pest management and is based on the principle of reducing insect pests by increasing the diversity of an ecosystem. On—farm experiments were conducted in villages of semi—arid tropical (SAT) India to identify the appropriate combination of castor (Ricinus communis L.) (Malpighiales: Euphorbiaceae) and intercropping in relation to pest incidence. The diversity created by introducing cluster bean, cowpea, black gram, or groundnut as intercrops in castor (1:2 ratio proportions) resulted in reduction of incidence of insect pests, namely semilooper (Achaea janata L.), leaf hopper (Empoasca flavescens Fabricius), and shoot and capsule borer (Conogethes punctiferalis Guenee). A buildup of natural enemies (Microplitis, coccinellids, and spiders) of the major pests of castor was also observed in these intercropping systems and resulted in the reduction of insect pests. Further, these systems were more efficient agronomically and economically, and were thus more profitable than a castor monocrop. PMID:22934569

Conservation planning on eroded land based of local wisdom in Kintamani sub-district, province of Bali

NASA Astrophysics Data System (ADS)

Sri Sumarniasih, Made; Antara, Made

2017-01-01

Location determination is based on the compilation of soil type’s map, land use map and slope map. Uniformity of soil type, slope and land use is classified into one unit of land, so that there are 48 units of land to be use as sample points. The purpose of this research are to identify patterns of land use, determine the amount of erosion, the amount of erosion that is tolerable and erosion control through a conservation plan based on local wisdom. The erosion prediction used USLE method, erosion of tolerated (Edp) using the formula Hammer. Results of laboratory and field observations having analyzed using USLE showed some level of erosion on land use in the Kintamani classified from very mild to very severe: 4.79 to 370.60 t ha-1yr-1, while Edp ranges from 30.00 to 48.00 t ha-1 yr-1. erosion Severe to very severe found on the use of mixed garden/citrus garden, dry land and shrubs/ reeds. The planned of use of land is intercropping annuals with horticultural crops (cabbage), citrus trees intercropped with flower of gumitir and bush land planting with elephant grass on a slope of less than 25% and planted of trees on land with a slope above 25%.

Improving intercropping: a synthesis of research in agronomy, plant physiology and ecology.

PubMed

Brooker, Rob W; Bennett, Alison E; Cong, Wen-Feng; Daniell, Tim J; George, Timothy S; Hallett, Paul D; Hawes, Cathy; Iannetta, Pietro P M; Jones, Hamlyn G; Karley, Alison J; Li, Long; McKenzie, Blair M; Pakeman, Robin J; Paterson, Eric; Schöb, Christian; Shen, Jianbo; Squire, Geoff; Watson, Christine A; Zhang, Chaochun; Zhang, Fusuo; Zhang, Junling; White, Philip J

2015-04-01

Intercropping is a farming practice involving two or more crop species, or genotypes, growing together and coexisting for a time. On the fringes of modern intensive agriculture, intercropping is important in many subsistence or low-input/resource-limited agricultural systems. By allowing genuine yield gains without increased inputs, or greater stability of yield with decreased inputs, intercropping could be one route to delivering ‘sustainable intensification’. We discuss how recent knowledge from agronomy, plant physiology and ecology can be combined with the aim of improving intercropping systems. Recent advances in agronomy and plant physiology include better understanding of the mechanisms of interactions between crop genotypes and species – for example, enhanced resource availability through niche complementarity. Ecological advances include better understanding of the context-dependency of interactions, the mechanisms behind disease and pest avoidance, the links between above- and below-ground systems, and the role of microtopographic variation in coexistence. This improved understanding can guide approaches for improving intercropping systems, including breeding crops for intercropping. Although such advances can help to improve intercropping systems, we suggest that other topics also need addressing. These include better assessment of the wider benefits of intercropping in terms of multiple ecosystem services, collaboration with agricultural engineering, and more effective interdisciplinary research.

Agroforestry management in vineyards: effects on soil microbial communities

NASA Astrophysics Data System (ADS)

Montagne, Virginie; Nowak, Virginie; Guilland, Charles; Gontier, Laure; Dufourcq, Thierry; Guenser, Josépha; Grimaldi, Juliette; Bourgade, Emilie; Ranjard, Lionel

2017-04-01

Some vineyard practices (tillage, chemical weeding or pest management) are generally known to impact the environment with particular negative effects on the diversity and the abundance of soil microorganisms, and cause water and soil pollutions. In an agro-ecological context, innovative cropping systems have been developed to improve ecosystem services. Among them, agroforestry offers strategies of sustainable land management practices. It consists in intercropping trees with annual/perennial/fodder crop on the same plot but it is weakly referenced with grapevine. The present study assesses the effects of intercropped and neighbouring trees on the soil of three agroforestry vineyards, in south-western France regions. More precisely soils of the different plots were sampled and the impact of the distance to the tree or to the neighbouring trees (forest) on soil microbial community has been considered. Indigenous soil microbial communities were characterized by a metagenomic approach that consisted in extracting the molecular microbial biomass, then in calculating the soil fungi/bacteria ratio - obtained by qPCR - and then in characterizing the soil microbial diversity - through Illumina sequencing of 16S and 18S regions. Our results showed a significant difference between the soil of agroforestry vineyards and the soil sampled in the neighbouring forest in terms of microbial abundance and diversity. However, only structure and composition of bacterial community seem to be influenced by the implanted trees in the vine plots. In addition, the comparison of microbial co-occurrence networks between vine and forest plots as well as inside vine plots according to distance to the tree allow revealing a more sensitive impact of agroforestry practices. Altogether, the results we obtained build up the first references for concerning the soil of agroforestry vineyards which will be interpreted in terms of soil quality, functioning and sustainability.

Economic Performance and Sustainability of a Novel Intercropping System on the North China Plain

PubMed Central

Huang, Chengdong; Liu, Quanqing; Heerink, Nico; Stomph, TjeerdJan; Li, Baoshen; Liu, Ruili; Zhang, Hongyan; Wang, Chong; Li, Xiaolin; Zhang, Chaochun; van der Werf, Wopke; Zhang, Fusuo

2015-01-01

Double cropping of wheat and maize is common on the North China Plain, but it provides limited income to rural households due to the small farm sizes in the region. Local farmers in Quzhou County have therefore innovated their production system by integration of watermelon as a companion cash crop into the system. We examine the economic performance and sustainability of this novel intercropping system using crop yield data from 2010 to 2012 and farm household survey data collected in 2012. Our results show that the gross margin of the intercropping system exceeded that of the double cropping system by more than 50% in 2012. Labor use in the intercropping system was more than three times that in double cropping. The lower returns per labor hour in intercropping, however, exceeded the average off-farm wage in the region by a significant margin. Nutrient surpluses and irrigation water use are significant larger under the intercropping system. We conclude that the novel wheat-maize/watermelon intercropping system contributes to rural poverty alleviation and household-level food security, by raising farm incomes and generating more employment, but needs further improvement to enhance its sustainability. PMID:26275297

Economic Performance and Sustainability of a Novel Intercropping System on the North China Plain.

PubMed

Huang, Chengdong; Liu, Quanqing; Heerink, Nico; Stomph, TjeerdJan; Li, Baoshen; Liu, Ruili; Zhang, Hongyan; Wang, Chong; Li, Xiaolin; Zhang, Chaochun; van der Werf, Wopke; Zhang, Fusuo

2015-01-01

Double cropping of wheat and maize is common on the North China Plain, but it provides limited income to rural households due to the small farm sizes in the region. Local farmers in Quzhou County have therefore innovated their production system by integration of watermelon as a companion cash crop into the system. We examine the economic performance and sustainability of this novel intercropping system using crop yield data from 2010 to 2012 and farm household survey data collected in 2012. Our results show that the gross margin of the intercropping system exceeded that of the double cropping system by more than 50% in 2012. Labor use in the intercropping system was more than three times that in double cropping. The lower returns per labor hour in intercropping, however, exceeded the average off-farm wage in the region by a significant margin. Nutrient surpluses and irrigation water use are significant larger under the intercropping system. We conclude that the novel wheat-maize/watermelon intercropping system contributes to rural poverty alleviation and household-level food security, by raising farm incomes and generating more employment, but needs further improvement to enhance its sustainability.

Effects of site preparation for pine forest/switchgrass Intercropping on water quality

Treesearch

A. Muwamba; D. M. Amatya; H. Ssegane; G.M. Chescheir; T. Appelboom; E.W. Tollner; J. E. Nettles; M. A. Youssef; F. Birgand; R. W. Skaggs; S. Tian

2015-01-01

A study was initiated to investigate the sustainability effects of intercropping switchgrass (Panicum virgatum L.) in a loblolly pine (Pinus taeda L.) plantation. This forest-based biofuel system could possibly provide biomass from the perennial energy grass while maintaining the economics and environmental benefits of a forest...

Conservation Agriculture Practices in Rainfed Uplands of India Improve Maize-Based System Productivity and Profitability

PubMed Central

Pradhan, Aliza; Idol, Travis; Roul, Pravat K.

2016-01-01

Traditional agriculture in rainfed uplands of India has been experiencing low agricultural productivity as the lands suffer from poor soil fertility, susceptibility to water erosion and other external pressures of development and climate change. A shift toward more sustainable cropping systems such as conservation agriculture production systems (CAPSs) may help in maintaining soil quality as well as improving crop production and farmer’s net economic benefit. This research assessed the effects over 3 years (2011–2014) of reduced tillage, intercropping, and cover cropping practices customized for maize-based production systems in upland areas of Odisha, India. The study focused on crop yield, system productivity and profitability through maize equivalent yield and dominance analysis. Results showed that maize grain yield did not differ significantly over time or among CAPS treatments while cowpea yield was considered as an additional yield in intercropping systems. Mustard and horsegram grown in plots after maize cowpea intercropping recorded higher grain yields of 25 and 37%, respectively, as compared to those without intercropping. Overall, the full CAPS implementation, i.e., minimum tillage, maize–cowpea intercropping and mustard residue retention had significantly higher system productivity and net benefits than traditional farmer practices, i.e., conventional tillage, sole maize cropping, and no mustard residue retention. The dominance analysis demonstrated increasing benefits of combining conservation practices that exceeded thresholds for farmer adoption. Given the use of familiar crops and technologies and the magnitude of yield and income improvements, these types of CAPS should be acceptable and attractive for smallholder farmers in the area. This in turn should support a move toward sustainable intensification of crop production to meet future household income and nutritional needs. PMID:27471508

Conservation Agriculture Practices in Rainfed Uplands of India Improve Maize-Based System Productivity and Profitability.

PubMed

Pradhan, Aliza; Idol, Travis; Roul, Pravat K

2016-01-01

Traditional agriculture in rainfed uplands of India has been experiencing low agricultural productivity as the lands suffer from poor soil fertility, susceptibility to water erosion and other external pressures of development and climate change. A shift toward more sustainable cropping systems such as conservation agriculture production systems (CAPSs) may help in maintaining soil quality as well as improving crop production and farmer's net economic benefit. This research assessed the effects over 3 years (2011-2014) of reduced tillage, intercropping, and cover cropping practices customized for maize-based production systems in upland areas of Odisha, India. The study focused on crop yield, system productivity and profitability through maize equivalent yield and dominance analysis. Results showed that maize grain yield did not differ significantly over time or among CAPS treatments while cowpea yield was considered as an additional yield in intercropping systems. Mustard and horsegram grown in plots after maize cowpea intercropping recorded higher grain yields of 25 and 37%, respectively, as compared to those without intercropping. Overall, the full CAPS implementation, i.e., minimum tillage, maize-cowpea intercropping and mustard residue retention had significantly higher system productivity and net benefits than traditional farmer practices, i.e., conventional tillage, sole maize cropping, and no mustard residue retention. The dominance analysis demonstrated increasing benefits of combining conservation practices that exceeded thresholds for farmer adoption. Given the use of familiar crops and technologies and the magnitude of yield and income improvements, these types of CAPS should be acceptable and attractive for smallholder farmers in the area. This in turn should support a move toward sustainable intensification of crop production to meet future household income and nutritional needs.

[Interspecific relationship and Si, N nutrition of rice in rice-water spinach intercropping system.

PubMed

Ning, Chuan Chuan; Yang, Rong Shuang; Cai, Mao Xia; Wang, Jian Wu; Luo, Shi Ming; Cai, Kun Zheng

2017-02-01

Intercropping is a sound eco-agriculture model, but aquatic crops (e.g., rice) intercropping is seldom researched. In the present study, rice and water spinach were chosen as the research objects, a field trial was conducted to explore the yields, interspecific relationship and Si, N nutrition of rice under rice-water spinach intercropping for four seasons during two consecutive years (2014-2015). The experiment had five treatments: rice monoculture, water spinach monoculture, and rice-water spinach intercropping ratios of 2:2, 3:2, 4:2, respectively. The results showed that rice-water spinach intercropping significantly increased rice yield, and the increase rates of 2:2, 3:2 and 4:2 intercropping per unit area were 77.5%-120.6%, 64.9%-80.9%, 37.7%-56.0%, respectively. However, intercropping resulted in reduction of water spinach yield. Intercropping significantly increased total yield of rice and water spinach from land equivalent ratios (LER) analysis. The values of LER were more than 1.0, and the ratio of 3:2 intercropping had the best effect. As for the competitive index, rice was more competitive than water spinach in intercropping system, especially in early season. Compared with rice monoculture, rice-water spinach intercropping significantly increased the absorption of Si and N in rice leaves, and Si content of rice leaves during ripening stage, but didn't increase its N content and even slightly reduced it during ripening stage. Intercropping had no significant effect on available Si, ammonium N and nitrate N content in soil. Compared with rice monoculture and intercropping, water spinach monoculture had always the highest available Si, ammonium N and nitrate N contents in soil through the experiment period. The results suggested that rice-spinach intercropping could promote rice to absorb silicon and nitrogen and increase the competitive ability of rice.

Legume-Cereal Intercropping Improves Forage Yield, Quality and Degradability.

PubMed

Zhang, Jie; Yin, Binjie; Xie, Yuhuai; Li, Jing; Yang, Zaibin; Zhang, Guiguo

2015-01-01

Intercropping legume with cereal is an extensively applied planting pattern in crop cultivation. However, forage potential and the degradability of harvested mixtures from intercropping system remain unclear. To investigate the feasibility of applying an intercropping system as a forage supply source to ruminants, two consecutive experiments (experiments 1 and 2) involving a field cultivation trial and a subsequent in vivo degradable experiment were conducted to determine the forage production performance and the ruminally degradable characteristics of a harvested mixture from an alfalfa/corn-rye intercropping system. In experiment 1, the intercropping system was established by alternating alfalfa and corn or rye with a row ratio of 5:2. Dry matter (DM) and nutrient yields were determined. In experiment 2, forages harvested from the different treatments were used as feedstuff to identify nutrient degradation kinetics and distribution of components between the rapidly degradable (a), potentially degradable (b) and the degradation rate constant (c) of 'b' fraction by in sacco method in Small-Tail Han wether Sheep. The intercropping system of alfalfa and corn-rye provided higher forage production performance with net increases of 9.52% and 34.81% in DM yield, 42.13% and 16.74% in crude protein (CP) yield, 25.94% and 69.99% in degradable DM yield, and 16.96% and 5.50% in degradable CP yield than rotation and alfalfa sole cropping systems, respectively. In addition, the harvest mixture from intercropping system also had greater 'a' fraction, 'b' fraction, 'c' values, and effective degradability (E value) of DM and CP than corn or rye hay harvested from rotation system. After 48-h exposure to rumen microbes, intercropping harvest materials were degraded to a higher extent than separately degraded crop stems from the sole system as indicated by visual microscopic examination with more tissues disappeared. Thus, the intercropping of alfalfa and corn-rye exhibited a greater forage production potential, and could be applied as forage supply source for ruminants. The improved effective degradability of harvest mixture material could be attributed to greater degradable components involving the rapidly degradable fractions (a), potentially degradable (b) fractions, and degradable rate constant (c), than that of corn and rye hay.

[Light competition and productivity of agroforestry system in loess area of Weibei in Shaanxi].

PubMed

Peng, Xiao-bang; Cai, Jing; Jiang, Zai-min; Zhang, Yuan-ying; Zhang, Shuo-xin

2008-11-01

Agroforestry is the most effective way for the restoration of disturbed land on Loess Plateau and the development of poorly local economy. Taking the tree-based intercropping systems of walnut or plum with soybean or pepper in the loess area of Weibei as test objects, the photosynthesis, growth, and yield of soybean (Qindou 8) and pepper (Shanjiao 981) in the systems were studied. The results showed that the photosynthetic active radiation (PAR), net photosynthetic rate (Pn), growth, and yield of individual soybean or pepper plants were significantly decreased, with the effects increased with decreasing distance from tree rows. Leaf water potential was not significantly or poorly correlated with the Pn, growth, and yield of the two crops. However, there were significant positive correlations between the soil moisture content in 10-20 cm layer and the biomass and yield of soybean, and the above-ground biomass of pepper. PAR was highly correlated with the yield of both crops, which indicated that light competition was one of the key factors leading to the decrease of crop yield.

Changes in soil organic carbon and total nitrogen in croplands converted to walnut-based agroforestry systems and orchards in southeastern Loess Plateau of China.

PubMed

Lu, Sen; Meng, Ping; Zhang, Jinsong; Yin, Changjun; Sun, Shiyou

2015-11-01

Limited information is available on the effects of agroforestry system practices on soil properties in the Loess Plateau of China. Over the last decade, a vegetation restoration project has been conducted in this area by converting cropland into tree-based agroforestry systems and orchards to combat soil erosion and degradation. The objective of the present study was to determine the effects of land use conversion on soil organic carbon and total nitrogen in southeastern Loess Plateau. The experiment included three treatments: walnut intercropping system (AF), walnut orchard (WO), and traditional cropland (CR). After 7 years of continual management, soil samples were collected at 0-10, 10-30, and 30-50-cm depths for three treatments, and soil organic carbon (SOC) and total nitrogen (TN) were measured. Results showed that compared with the CR and AF treatments, WO treatment decreased both SOC and TN concentrations in the 0-50-cm soil profile. However, similar patterns of SOC and TN concentrations were observed in the AF and CR treatments across the entire profile. The SOC stocks at 0-50-cm depth were 5.42, 5.52, and 4.67 kg m(-2) for CR, AF, and WO treatments, respectively. The calculated TN stocks at 0-50-cm depth were 0.63, 0.62, and 0.57 kg m(-2) for CR, AF, and WO treatments, respectively. This result demonstrated that the stocks of SOC and TN in WO were clearly lower than those of AF and CR and that the walnut-based agroforestry system was more beneficial than walnut monoculture in terms of SOC and TN sequestration. Owing to the short-term intercropping practice, the changes in SOC and TN stocks were slight in AF compared with those in CR. However, a significant decrease in SOC and TN stocks was observed during the conversion of cropland to walnut orchard after 7 years of management. We also found that land use types had no significant effect on soil C/N ratio. These findings demonstrated that intercropping between walnut rows can potentially maintain more SOC and TN stocks than walnut monoculture and that agroforestry is a sustainable management pattern for vegetation restoration in the Loess Plateau area.

Soil microflora and enzyme activities in rhizosphere of Transgenic Bt cotton hybrid under different intercropping systems and plant protection schedules

NASA Astrophysics Data System (ADS)

Biradar, D. P.; Alagawadi, A. R.; Basavanneppa, M. A.; Udikeri, S. S.

2012-04-01

Field experiments were conducted over three rainy seasons of 2005-06 to 2007-08 on a Vertisol at Dharwad, Karnataka, India to study the effect of intercropping and plant protection schedules on productivity, soil microflora and enzyme activities in the rhizosphere of transgenic Bt cotton hybrid. The experiment consisted of four intercropping systems namely, Bt cotton + okra, Bt cotton + chilli, Bt cotton + onion + chilli and Bt cotton + redgram with four plant protection schedules (zero protection, protection for Bt cotton, protection for intercrop and protection for both crops). Observations on microbial populations and enzyme activities were recorded at 45, 90, 135 and 185 (at harvest) days after sowing (DAS). Averaged over years, Bt cotton + okra intercropping had significantly higher total productivity than Bt cotton + chilli and Bt cotton + redgram intercropping system and was similar to Bt cotton + chilli + onion intercropping system. With respect to plant protection schedules for bollworms, protection for both cotton and intercrops recorded significantly higher yield than the rest of the treatments. Population of total bacteria, fungi, actinomycetes, P-solubilizers, free-living N2 fixers as well as urease, phosphatase and dehydrogenase enzyme activities increased up to 135 days of crop growth followed by a decline. Among the intercropping systems, Bt cotton + chilli recorded significantly higher population of microorganisms and enzyme activities than other cropping systems. While Bt cotton with okra as intercrop recorded the least population of total bacteria and free-living N2 fixers as well as urease activity. Intercropping with redgram resulted in the least population of actinomycetes, fungi and P-solubilizers, whereas Bt cotton with chilli and onion recorded least activities of dehydrogenase and phosphatase. Among the plant protection schedules, zero protection recorded maximum population of microorganisms and enzyme activities. This was followed by the plant protection schedule taken up for main crop and for intercrops, but was least in the insecticide sprayed to both the crops. Data on interaction of intercropping and plant protection schedules indicated that Bt cotton with chilli as intercrop and with zero plant protection showed the highest population of P-solubilizers, N2 fixers as well as urease and phosphatase activities at 135 days of crop growth. Similarly, population of total bacteria, fungi and actinomycetes were highest in the treatment of Bt cotton + chilli + onion with zero protection but were on par with the treatment Bt cotton + chilli with zero protection at 135 days of crop growth. Dehydrogenase activity was found to be the highest in the treatment of Bt cotton + redgram with zero protection at 135 days of crop growth. Our studies showed harmful effects of insecticide sprays on soil microflora and enzyme activities.

Sward characteristics and performance of dairy cows in organic grass-legume pastures shaded by tropical trees.

PubMed

Paciullo, D S C; Pires, M F A; Aroeira, L J M; Morenz, M J F; Maurício, R M; Gomide, C A M; Silveira, S R

2014-08-01

The silvopastoral system (SPS) has been suggested to ensure sustainability in animal production systems in tropical ecosystems. The objective of this study was to evaluate pasture characteristics, herbage intake, grazing activity and milk yield of Holstein×Zebu cows managed in two grazing systems (treatments): SPS dominated by a graminaceous forage (Brachiaria decumbens) intercropped with different leguminous herbaceous forages (Stylosanthes spp., Pueraria phaseoloides and Calopogonium mucunoides) and legume trees (Acacia mangium, Gliricidia sepium and Leucaena leucocephala), and open pasture (OP) of B. decumbens intercropped only with Stylosanthes spp. Pastures were managed according to the rules for organic cattle production. The study was carried out by following a switch back format with 12 cows, 6 for each treatment, over 3 experimental years. Herbage mass was similar (P>0.05) for both treatments, supporting an average stocking rate of 1.23 AU/ha. Daily dry matter intake did not vary (P>0.05) between treatments (average of 11.3±1.02 kg/cow per day, corresponding to 2.23±0.2% BW). Milk yield was higher (P0.05) in subsequent years. The highest (P0.05) milk yields. Low persistence of Stylosanthes guianensis was observed over the experimental period, indicating that the persistence of forage legumes under grazing could be improved using adapted cultivars that have higher annual seed production. The SPS and a diversified botanical composition of the pasture using legume species mixed with grasses are recommended for organic milk production.

Water use efficiency and evapotranspiration in maize-soybean relay strip intercrop systems as affected by planting geometries.

PubMed

Rahman, Tanzeelur; Liu, Xin; Hussain, Sajad; Ahmed, Shoaib; Chen, Guopeng; Yang, Feng; Chen, Lilian; Du, Junbo; Liu, Weiguo; Yang, Wenyu

2017-01-01

Optimum planting geometries have been shown to increase crop yields in maize-soybean intercrop systems. However, little is known about whether changes in planting geometry improve the seasonal water use of maize and soybean intercrops. We conducted two different field experiments in 2013 and 2014 to investigate the effects of changes in planting geometry on water use efficiency (WUE) and evapotranspiration (ETc) of maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] relay strip intercrop systems. Our results showed that the leaf area index of maize for both years where intercropping occurred was notably greater compared to sole maize, thus the soil water content (SWC), soil evaporation (E), and throughfall followed a decreasing trend in the following order: central row of maize strip (CRM) < adjacent row between maize and soybean strip (AR) < central row of soybean strip (CRS). When intercropped, the highest grain yield for maize and total yields were recorded for the 40:120 cm and 40:160 cm planting geometries using 160 cm and 200 cm bandwidth, respectively. By contrast, the highest grain yield of intercropped soybean was appeared for the 20:140 cm and 20:180 cm planting geometries. The largest land equivalent ratios were 1.62 for the 40:120 cm planting geometry and 1.79 for the 40:160 cm planting geometry, indicating that both intercropping strategies were advantageous. Changes in planting geometries did not show any significant effect on the ETc of the maize and soybean intercrops. WUEs in the different planting geometries of intercrop systems were lower compared to sole cropping. However, the highest group WUEs of 23.06 and 26.21 kg ha-1 mm-1 for the 40:120 cm and 40:160 cm planting geometries, respectively, were 39% and 23% higher than those for sole cropping. Moreover, the highest water equivalent ratio values of 1.66 and 1.76 also appeared for the 40:120 cm and 40:160 cm planting geometries. We therefore suggest that an optimum planting geometry of 40:160 cm and bandwidth of 200 cm could be a viable planting pattern management method for attaining high group WUE in maize-soybean intercrop systems.

Intercropping of green garlic (Allium sativum L.) induces nutrient concentration changes in the soil and plants in continuously cropped cucumber (Cucumis sativus L.) in a plastic tunnel.

PubMed

Xiao, Xuemei; Cheng, Zhihui; Meng, Huanwen; Liu, Lihong; Li, Hezi; Dong, Yinxin

2013-01-01

A pot-based experiment was conducted to investigate nutrient concentrations in cucumber plants intercropped with various amounts of green garlic. In addition, the soil nutrient contents were studied over two consecutive growing seasons. The results revealed that the accumulation of biomass and the nutritional elements nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and manganese (Mn) in cucumber plants were significantly increased for intercropping treatments during the two growing seasons compared to monoculture. Conversely, magnesium (Mg) concentrations were decreased in the cucumber plants. Shoot iron (Fe) concentrations decreased whereas root Fe concentrations increased in the intercropping system. Shoot and root zinc (Zn) concentrations decreased during the fall of 2011 but increased during the spring of 2012. Soil organic matter and available N, P and K were significantly increased as the proportion of intercropped green garlic increasing. Medium levels of intercropping green garlic improved cucumber nutrient concentrations the most. The regression analysis showed that the concentrations of most elements were significantly related to the amounts of garlic bulbs, especially the microelements in the spring 2011. The available soil N and organic matter were linearly related to the amounts of garlic bulbs. The results indicate that the nutritional status of the soil and plants of continuously cropped cucumber could be improved by intercropping with green garlic.

Intercropping of Green Garlic (Allium sativum L.) Induces Nutrient Concentration Changes in the Soil and Plants in Continuously Cropped Cucumber (Cucumis sativus L.) in a Plastic Tunnel

PubMed Central

Xiao, Xuemei; Cheng, Zhihui; Meng, Huanwen; Liu, Lihong; Li, Hezi; Dong, Yinxin

2013-01-01

A pot-based experiment was conducted to investigate nutrient concentrations in cucumber plants intercropped with various amounts of green garlic. In addition, the soil nutrient contents were studied over two consecutive growing seasons. The results revealed that the accumulation of biomass and the nutritional elements nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and manganese (Mn) in cucumber plants were significantly increased for intercropping treatments during the two growing seasons compared to monoculture. Conversely, magnesium (Mg) concentrations were decreased in the cucumber plants. Shoot iron (Fe) concentrations decreased whereas root Fe concentrations increased in the intercropping system. Shoot and root zinc (Zn) concentrations decreased during the fall of 2011 but increased during the spring of 2012. Soil organic matter and available N, P and K were significantly increased as the proportion of intercropped green garlic increasing. Medium levels of intercropping green garlic improved cucumber nutrient concentrations the most. The regression analysis showed that the concentrations of most elements were significantly related to the amounts of garlic bulbs, especially the microelements in the spring 2011. The available soil N and organic matter were linearly related to the amounts of garlic bulbs. The results indicate that the nutritional status of the soil and plants of continuously cropped cucumber could be improved by intercropping with green garlic. PMID:23637994

[Effects of reduced N application rate on yield and nutrient uptake and utilization in maize-soybean relay strip intercropping system].

PubMed

Yong, Tai-Wen; Liu, Xiao-Ming; Wen-Yu, Liu; Su, Ben-Ying; Song, Chun; Yang, Feng; Wang, Xiao-Chun; Yang, Wen-Yu

2014-02-01

A field experiment with three N application rates (0, 180, 240 N kg x hm(-2), representing zero, reduced and conventional N application, respectively) and three planting patterns (maize monoculture, soybean monoculture and maize-soybean relay strip intercropping) was conducted to reveal the effects of cropping patterns and N application rates on yield, nutrient uptake and nitrogen use efficiency of maize and soybean. The results showed that the grain yield, N, P and K uptake and harvest index of the intercropped maize reduced slightly compared with the monoculture maize, however these indices of the intercropped soybean increased significantly compared with the monoculture. With the increase in nitrogen fertilizer application, the excellence of relay strip intercropping was weakened in the maize-soybean intercropping system. The grain yield, economic coefficient, N, P and K uptake, harvest index, N agronomy efficiency and N uptake efficiency of maize and soybean increased significantly at the reduced nitrogen rate (180 N kg x hm(-2)), but the rate of soil N contribution declined, compared with the conventional rate of N application by local farmers (240 N kg x hm(-2)). In the reduced nitrogen rate treatment, total soil N and P contents of the maize strip reduced, whereas the total soil N, P and K contents of soybean strip and the total K content of maize strip increased compared with the zero N application treatment. With the reduced N application, the annual total grain yield, N, P and K uptake of above-ground biomass in the maize-soybean relay strip intercropping system were higher than in the monoculture, and the land equivalent ratio (LER) was 2.28. N uptake efficiency of maize in the relay strip intercropping system was 20.2% higher than in the maize monoculture, and the index of soybean was 30.5% lower than in the monoculture. The rate of soil N contribution in the relay strip intercropping system was 20.0% and 8.8% lower than in the maize and soybean monoculture, respectively. The reduced N application in the maize-soybean relay strip intercropping system was helpful to promote annual grain yield and improve N utilization efficiency.

Watershed-scale Hydrology and Water Quality Impact of Switchgrass Intercropping in Southern Managed Pine Forests

NASA Astrophysics Data System (ADS)

Chescheir, G. M.; Birgand, F.; Allen, E.; Bennett, E.; Carter, T.; Dobbs, N.; Muwamba, A.; Amatya, D. M.; Youssef, M.; Nettles, J. E.

2016-12-01

The use of marginal land for cellulosic biofuel crop production is an attractive solution to preserve agricultural land for food production. The space available between rows of young loblolly pine (Pinus taeda) trees offers enough light to support growth of biofuel crops for several years. A five year field study was conducted to assess the hydrology and water quality impacts of switchgrass (Panicum virgatum) intercropping with pine trees in watersheds of the southeastern US. Paired-watershed studies were replicated in Mississippi and Alabama on upland sites, and in North Carolina on a flat lowland site. In each state, the impact of switchgrass intercropping was assessed from differences in water and nutrient yields from contiguous 20-40 ha watersheds established as: conventional young pine plantation, switchgrass intercropped in young pine plantation, switchgrass only, and mid-rotation mature pine plantation. A total of 14 watersheds were equipped with continuous flow monitoring stations, flow proportional water samplers, groundwater wells, soil moisture sensors and weather stations. Data collection continued through a two year pre-treatment period, a one year treatment period when field operations were conducted to establish switchgrass, and a two year post-treatment period when the established switchgrass was fertilized and harvested annually. Our results showed that significant increases in total suspended solids (TSS) and nitrogen (N) loading occurred during the treatment periods at the upland sites in MS and AL. During the post treatment periods, TSS and N loading decreased to levels near those observed in pretreatment. At the lowland site, only nitrogen loading was increased during the treatment period. Concentrations of TSS at the lowland site were two orders of magnitude lower than those observed at the upland sites and were not significantly affected by the treatment. Inherent flow variability between watersheds within sites made detection of subtle differences in hydrology and water quality difficult to detect. Increases in N loading were not significant in response to annual fertilization of switchgrass. Our results suggest that intercropping switchgrass in managed pine forests does not significantly change the typically benign hydrology and water quality of the managed forests.

Maize-grain legume intercropping for enhanced resource use efficiency and crop productivity in the Guinea savanna of northern Ghana.

PubMed

Kermah, Michael; Franke, Angelinus C; Adjei-Nsiah, Samuel; Ahiabor, Benjamin D K; Abaidoo, Robert C; Giller, Ken E

2017-11-01

Smallholder farmers in the Guinea savanna practise cereal-legume intercropping to mitigate risks of crop failure in mono-cropping. The productivity of cereal-legume intercrops could be influenced by the spatial arrangement of the intercrops and the soil fertility status. Knowledge on the effect of soil fertility status on intercrop productivity is generally lacking in the Guinea savanna despite the wide variability in soil fertility status in farmers' fields, and the productivity of within-row spatial arrangement of intercrops relative to the distinct-row systems under on-farm conditions has not been studied in the region. We studied effects of maize-legume spatial intercropping patterns and soil fertility status on resource use efficiency, crop productivity and economic profitability under on-farm conditions in the Guinea savanna. Treatments consisted of maize-legume intercropped within-row, 1 row of maize alternated with one row of legume, 2 rows of maize alternated with 2 rows of legume, a sole maize crop and a sole legume crop. These were assessed in the southern Guinea savanna (SGS) and the northern Guinea savanna (NGS) of northern Ghana for two seasons using three fields differing in soil fertility in each agro-ecological zone. Each treatment received 25 kg P and 30 kg K ha -1 at sowing, while maize received 25 kg (intercrop) or 50 kg (sole) N ha -1 at 3 and 6 weeks after sowing. The experiment was conducted in a randomised complete block design with each block of treatments replicated four times per fertility level at each site. Better soil conditions and rainfall in the SGS resulted in 48, 38 and 9% more maize, soybean and groundnut grain yield, respectively produced than in the NGS, while 11% more cowpea grain yield was produced in the NGS. Sole crops of maize and legumes produced significantly more grain yield per unit area than the respective intercrops of maize and legumes. Land equivalent ratios (LERs) of all intercrop patterns were greater than unity indicating more efficient and productive use of environmental resources by intercrops. Sole legumes intercepted more radiation than sole maize, while the interception by intercrops was in between that of sole legumes and sole maize. The intercrop however converted the intercepted radiation more efficiently into grain yield than the sole crops. Economic returns were greater for intercrops than for either sole crop. The within-row intercrop pattern was the most productive and lucrative system. Larger grain yields in the SGS and in fertile fields led to greater economic returns. However, intercropping systems in poorly fertile fields and in the NGS recorded greater LERs (1.16-1.81) compared with fertile fields (1.07-1.54) and with the SGS. This suggests that intercropping is more beneficial in less fertile fields and in more marginal environments such as the NGS. Cowpea and groundnut performed better than soybean when intercropped with maize, though the larger absolute grain yields of soybean resulted in larger net benefits.

Variation of Bacterial Community Diversity in Rhizosphere Soil of Sole-Cropped versus Intercropped Wheat Field after Harvest.

PubMed

Yang, Zhenping; Yang, Wenping; Li, Shengcai; Hao, Jiaomin; Su, Zhifeng; Sun, Min; Gao, Zhiqiang; Zhang, Chunlai

2016-01-01

As the major crops in north China, spring crops are usually planted from April through May every spring and harvested in fall. Wheat is also a very common crop traditionally planted in fall or spring and harvested in summer year by year. This continuous cropping system exhibited the disadvantages of reducing the fertility of soil through decreasing microbial diversity. Thus, management of microbial diversity in the rhizosphere plays a vital role in sustainable crop production. In this study, ten common spring crops in north China were chosen sole-cropped and four were chosen intercropped with peanut in wheat fields after harvest. Denaturing gradient gel electrophoresis (DGGE) and DNA sequencing of one 16S rDNA fragment were used to analyze the bacterial diversity and species identification. DGGE profiles showed the bacterial community diversity in rhizosphere soil samples varied among various crops under different cropping systems, more diverse under intercropping system than under sole-cropping. Some intercropping-specific bands in DGGE profiles suggested that several bacterial species were stimulated by intercropping systems specifically. Furthermore, the identification of these dominant and functional bacteria by DNA sequencing indicated that intercropping systems are more beneficial to improve soil fertility. Compared to intercropping systems, we also observed changes in microbial community of rhizosphere soil under sole-crops. The rhizosphere bacterial community structure in spring crops showed a strong crop species-specific pattern. More importantly, Empedobacter brevis, a typical plant pathogen, was only found in the carrot rhizosphere, suggesting carrot should be sown prudently. In conclusion, our study demonstrated that crop species and cropping systems had significant effects on bacterial community diversity in the rhizosphere soils. We strongly suggest sorghum, glutinous millet and buckwheat could be taken into account as intercropping crops with peanut; while hulled oat, mung bean or foxtail millet could be considered for sowing in wheat fields after harvest in North China.

Row Ratios of Intercropping Maize and Soybean Can Affect Agronomic Efficiency of the System and Subsequent Wheat

PubMed Central

Zhang, Yitao; Liu, Jian; Zhang, Jizong; Liu, Hongbin; Liu, Shen; Zhai, Limei; Wang, Hongyuan; Lei, Qiuliang; Ren, Tianzhi; Yin, Changbin

2015-01-01

Intercropping is regarded as an important agricultural practice to improve crop production and environmental quality in the regions with intensive agricultural production, e.g., northern China. To optimize agronomic advantage of maize (Zea mays L.) and soybean (Glycine max L.) intercropping system compared to monoculture of maize, two sequential experiments were conducted. Experiment 1 was to screening the optimal cropping system in summer that had the highest yields and economic benefits, and Experiment 2 was to identify the optimum row ratio of the intercrops selected from Experiment 1. Results of Experiment 1 showed that maize intercropping with soybean (maize || soybean) was the optimal cropping system in summer. Compared to conventional monoculture of maize, maize || soybean had significant advantage in yield, economy, land utilization ratio and reducing soil nitrate nitrogen (N) accumulation, as well as better residual effect on the subsequent wheat (Triticum aestivum L.) crop. Experiment 2 showed that intercropping systems reduced use of N fertilizer per unit land area and increased relative biomass of intercropped maize, due to promoted photosynthetic efficiency of border rows and N utilization during symbiotic period. Intercropping advantage began to emerge at tasseling stage after N topdressing for maize. Among all treatments with different row ratios, alternating four maize rows with six soybean rows (4M:6S) had the largest land equivalent ratio (1.30), total N accumulation in crops (258 kg ha-1), and economic benefit (3,408 USD ha-1). Compared to maize monoculture, 4M:6S had significantly lower nitrate-N accumulation in soil both after harvest of maize and after harvest of the subsequent wheat, but it did not decrease yield of wheat. The most important advantage of 4M:6S was to increase biomass of intercropped maize and soybean, which further led to the increase of total N accumulation by crops as well as economic benefit. In conclusion, alternating four maize rows with six soybean rows was the optimum row ratio in maize || soybean system, though this needs to be further confirmed by pluri-annual trials. PMID:26061566

Agronomic viability of New Zealand spinach and kale intercropping.

PubMed

Cecílio, Arthur B; Bianco, Matheus S; Tardivo, Caroline F; Pugina, Gabriel C M

2017-01-01

The intercropping is a production system that aims to provide increased yield with less environmental impact, due to greater efficiency in the use of natural resources and inputs involved in the production process. An experiment was carried out to evaluate the agronomic viability of kale and New Zealand spinach intercropping as a function of the spinach transplanting time. (0, 14, 28, 42, 56, 70, 84 and 98 days after transplanting of the kale). The total yield (TY) and yield per harvest (YH) of the kale in intercropping did not differ from those obtained in monoculture. The spinach TY was influenced by the transplanting time, the earlier the transplanting, the higher the TY. The spinach YH was not influenced by the transplanting time, but rather by the cultivation system. In intercropping, the spinach YH was 13.5% lower than in monoculture. The intercropping was agronomically feasible, since the land use efficiency index, which was not influenced by the transplanting time, had an average value of 1.71, indicating that the intercropping produced 71% more kale and spinach than the same area in monoculture. Competitiveness coefficient, aggressiveness and yield loss values showed that kale is the dominating species and spinach is the dominated.

Evapotranspiration of a pine-switchgrass intercropping bioenergy system measured by combined surface renewal and energy balance method

NASA Astrophysics Data System (ADS)

Fischer, M.; Noormets, A.; Domec, J. C.; Rosa, R.; Williamson, J.; Boone, J.; Sucre, E.; Trnka, M.; King, J.

2015-12-01

Intercropping bioenergy grasses within traditional pine silvicultural systems provides an opportunity for economic diversification and regional bioenergy production in a way that complements existing land use systems. Bioenergy intercropping in pine plantations does not compete with food production for land and it is thought will increase ecosystem resource-use efficiencies. As the frequency and intensity of drought is expected to increase with the changing climate, maximizing water use-efficiency of intercropped bioenergy systems will become increasingly important for long-term economic and environmental sustainability. The presented study is focused on evapotranspiration (ET) of an experimental pine-switchgrass intercropping system in the Lower Coastal Plain of North Carolina. We measured ET of two pure switchgrass fields, two pure pine stands and two pine-switchgrass intercropping systems using combined surface renewal (SR) and energy balance (EB) method throughout 2015. SR is based on high-frequency measurement of air temperature at or above canopy. As previously demonstrated, temperature time series are associated with identifiable, repeated patterns called "turbulent coherent structures". These coherent structures are considered to be responsible for most of the turbulent transport. Statistical analysis of the coherent structures in temperature time series allows quantification of sensible heat flux density (H) from the investigated area. Information about H can be combined with measurement of net radiation and soil heat flux density to indirectly obtain ET estimates as a residual of the energy balance equation. Despite the recent progress in the SR method, there is no standard methodology and each method available includes assumptions which require more research. To validate our SR estimates of ET, we used an eddy covariance (EC) system placed temporarily next to the each SR station as a comparative measurement of H. The conference contribution will include: i) evaluation of SR method compared to EC; ii) comparison of different SR calculation procedures including application of various thermocouples sizes and measurement heights; iii) quantification of ET of the three investigated ecosystems; iv) analysis of ET diurnal and seasonal variation with respect to weather conditions.

[Relationships between soil nutrients and rhizospheric soil microbial communities and enzyme activities in a maize-capsicum intercropping system].

PubMed

Xu, Qiang; Cheng, Zhi-Hui; Meng, Huan-Wen; Zhang, Yu

2007-12-01

By using plastic sheet and nylon mesh to partition the root systems of maize and capsicum in a maize-capsicum intercropping system, this paper studied the relationships between soil biological factors and nutritive status in the intercropping system, with no partitioning and maize monoculture and capsicum monoculture as the control. The results showed that intercropping maize and capsicum had its high superiority. In the treatments of no partitioning and nylon mesh portioning in the intercropping system, soil enzyme activities, microbial individuals and nutrient contents were significantly higher, compared with those in the treatments of nylon mesh partitioning and monocultures. All kinds of soil available nutrients showed significant or very significant positive correlations with soil biological factors, except that soil available Mg was negatively correlated with soil fungi and catalase activity. Pathway analysis indicated that in the intercropping system, soil urease, catalase, protease, and bacteria were the main factors affecting the accumulation of soil organic matter, saccharase was the most important factor affecting soil alkali-hydrolyzable N, urease was the most important factor affecting soil available P, and bacteria largely determined soil available K. Soil alkaline phosphatase and fungi selectively affected the accumulation of soil organic matter and available N, P and K. There was a slight negative correlation between soil actinomycetes and soil nutrients, suggesting that actinomycetes had little effect on soil nutrient formation.

Intercropped watermelon for weed suppression in a low-input organic system.

USDA-ARS?s Scientific Manuscript database

A multi-layered canopy provided by intercropping species with different growth forms can provide barriers for the germination of weed seeds and can allow for a more efficient utilization of resources that reduce competition to target crops from weeds. Intercropping can thus be an effective cultural ...

Push-Pull: Chemical Ecology-Based Integrated Pest Management Technology.

PubMed

Khan, Zeyaur; Midega, Charles A O; Hooper, Antony; Pickett, John

2016-07-01

Lepidopterous stemborers, and parasitic striga weeds belonging to the family Orobanchaceae, attack cereal crops in sub-Saharan Africa causing severe yield losses. The smallholder farmers are resource constrained and unable to afford expensive chemicals for crop protection. The push-pull technology, a chemical ecology- based cropping system, is developed for integrated pest and weed management in cereal-livestock farming systems. Appropriate plants were selected that naturally emit signaling chemicals (semiochemicals). Plants highly attractive for stemborer egg laying were selected and employed as trap crops (pull), to draw pests away from the main crop. Plants that repelled stemborer females were selected as intercrops (push). The stemborers are attracted to the trap plant, and are repelled from the main cereal crop using a repellent intercrop (push). Root exudates of leguminous repellent intercrops also effectively control the parasitic striga weed through an allelopathic mechanism. Their root exudates contain flavonoid compounds some of which stimulate germination of Striga hermonthica seeds, such as Uncinanone B, and others that dramatically inhibit their attachment to host roots, such as Uncinanone C and a number of di-C-glycosylflavones (di-CGFs), resulting in suicidal germination. The intercrop also improves soil fertility through nitrogen fixation, natural mulching, improved biomass, and control of erosion. Both companion plants provide high value animal fodder, facilitating milk production and diversifying farmers' income sources. The technology is appropriate to smallholder mixed cropping systems in Africa. Adopted by about 125,000 farmers to date in eastern Africa, it effectively addresses major production constraints, significantly increases maize yields, and is economical as it is based on locally available plants, not expensive external inputs.

[Effect of reduced N application on soil N residue and N loss in maize-soybean relay strip intercropping system].

PubMed

Liu, Xiao-Ming; Yong, Tai-Wen; Liu, Wen-Yu; Su, Ben-Ying; Song, Chun; Yang, Feng; Wang, Xiao-Chun; Yang, Wen-Yu

2014-08-01

A field experiment was conducted in 2012, including three planting pattern (maize-soybean relay strip intercropping, mono-cultured maize and soybean) and three nitrogen application level [0 kg N x hm(-2), 180 kg N x hm(-2) (reduced N) and 240 kg N x hm(-2) (normal N)]. Fields were assigned to different treatments in a randomized block design with three replicates. The objective of this work was to analyze the effects of planting patterns and nitrogen application rates on plant N uptake, soil N residue and N loss. After fertilization applications, NH4(+)-N and NO3(-)-N levels increased in the soil of intercropped maize but decreased in the soil of intercropped soybean. Compared with mono-crops, the soil N residue and loss of intercropped soybean were reduced, while those of intercropped maize were increased and decreased, respectively. With the reduced rate of N application, N residue rate, N loss rate and ammonia volatilization loss rate of the maize-soybean intercropping relay strip system were decreased by 17.7%, 21.5% and 0.4% compared to mono-cultured maize, but increased by 2.0%, 19.8% and 0.1% compared to mono-cultured soybean, respectively. Likewise, the reduced N application resulted in reductions in N residue, N loss, and the N loss via ammonia volatilization in the maize-soybean relay strip intercropping system compared with the conventional rate of N application adopted by local farmers, and the N residue rate, N loss rate and ammonia volatilization loss rate reduced by 12.0%, 15.4% and 1.2%, respectively.

Comparison of measured changes in seasonal soil water content by rainfed maize-bean intercrop and component cropping systems in a semi-arid region of southern Africa

NASA Astrophysics Data System (ADS)

Ogindo, H. O.; Walker, S.

Seasonal water content fluctuation within the effective root zone was monitored during the growing season for a maize-bean intercrop (IMB), sole maize (SM) and sole bean (SB) in Free State Province, Republic of South Africa. Comparisons were undertaken for progressive depths of extraction 0-300 mm; 300-600 mm and 600-900 mm respectively. These enabled the understanding of water extraction behavior of the cropping systems within the different soil layers including the topsoil surface normally influenced by soil surface evaporation. Additive intercrops have been known to conserve water, largely due to the early high leaf area index and the higher total leaf area. In this study, the combined effect of the intercrop components seemed to lower the total water demand by the intercrop compared to the sole crops. During the two seasons (2000/2001 and 2001/2002) the drained upper limit (DUL) and crop lower limits (CLL) were determined. The maize-bean intercrop, sole maize and sole bean had CLL of 141 mm/m, 149 mm/m and 159 mm/m respectively. The DUL was 262 mm/m for the site and therefore the potential plant extractable soil water for the cropping systems were: 121 mm/m (IMB); 114 mm/m (SM) and 103 mm/m (SB). Overall, the intercrop did not have significantly different total soil water extraction during both seasons, although it was additive, showing that it had higher water to biomass conversion.

[Changes of soil physical properties during the conversion of cropland to agroforestry system].

PubMed

Wang, Lai; Gao, Peng Xiang; Liu, Bin; Zhong, Chong Gao; Hou, Lin; Zhang, Shuo Xin

2017-01-01

To provide theoretical basis for modeling and managing agroforestry systems, the influence of conversion of cropland to agroforestry system on soil physical properties was investigated via a walnut (Juglans regia)-wheat (Triticum aestivum) intercropping system, a wide spreading local agroforestry model in northern Weihe River of loess area, with the walnut and wheat monoculture systems as the control. The results showed that the improvement of the intercropping system on soil physical properties mainly appeared in the 0-40 cm soil layer. The intercropping system could prevent soil bulk density rising in the surface soil (0-20 cm), and the plow pan in the 20-40 cm soil layer could be significantly alleviated. The intercropping system had conti-nuous improvement on soil field capacity in each soil layer with the planting age increase, and the soil field capacity was higher than that of each monoculture system in each soil layer (except 20-40 cm soil layer) since the 5th year after planting. The intercropping system had continuous improvement on soil porosity in each soil layer, but mainly in the 0-20 and 20-40 cm soil layer, and the ratio of capillary porosity was also improved. The soil bulk density, field capacity and soil porosity obtained continuous improvement during the conversion of cropland to agroforestry system, and the improvement on soil physical properties was stronger in shallow soil layer than in deep soil.

Cropping system diversification for food production in Mindanao rubber plantations: a rice cultivar mixture and rice intercropped with mungbean

PubMed Central

Elazegui, Francisco; Duque, Jo-Anne Lynne Joy E.; Mundt, Christopher C.; Vera Cruz, Casiana M.

2017-01-01

Including food production in non-food systems, such as rubber plantations and biofuel or bioenergy crops, may contribute to household food security. We evaluated the potential for planting rice, mungbean, rice cultivar mixtures, and rice intercropped with mungbean in young rubber plantations in experiments in the Arakan Valley of Mindanao in the Philippines. Rice mixtures consisted of two- or three-row strips of cultivar Dinorado, a cultivar with higher value but lower yield, and high-yielding cultivar UPL Ri-5. Rice and mungbean intercropping treatments consisted of different combinations of two- or three-row strips of rice and mungbean. We used generalized linear mixed models to evaluate the yield of each crop alone and in the mixture or intercropping treatments. We also evaluated a land equivalent ratio for yield, along with weed biomass (where Ageratum conyzoides was particularly abundant), the severity of disease caused by Magnaporthe oryzae and Cochliobolus miyabeanus, and rice bug (Leptocorisa acuta) abundance. We analyzed the yield ranking of each cropping system across site-year combinations to determine mean relative performance and yield stability. When weighted by their relative economic value, UPL Ri-5 had the highest mean performance, but with decreasing performance in low-yielding environments. A rice and mungbean intercropping system had the second highest performance, tied with high-value Dinorado but without decreasing relative performance in low-yielding environments. Rice and mungbean intercropped with rubber have been adopted by farmers in the Arakan Valley. PMID:28194318

Temporal dynamics of the arthropod community in pear orchards intercropped with aromatic plants.

PubMed

Beizhou, Song; Jie, Zhang; Jinghui, Hu; Hongying, Wu; Yun, Kong; Yuncong, Yao

2011-09-01

Increasing attention has been paid to enhancing biological control through habitat management in agricultural systems for enhanced pest management. Pest management benefits can be realised by intercropping, which can increase natural enemy abundance and, in turn, reduce pest abundance. In this study, the composition and temporal dynamics of arthropod communities in pear orchards when intercropped with aromatic plants were investigated, and the effectiveness and applicability of aromatic plants as intercrops for enhancing insect control were assessed. When compared with natural grasses or clean tillage, intercropping significantly reduced pest abundance and increased the ratio of natural enemies to pests. Intercropping also shortened the occurrence duration and depressed the incidence peak in annual dynamics curves of the pest subcommunity and the arthropod community, mainly because of the repellent effects of aromatic plants. Equally important, intercropping significantly reduced the numbers of major pests, such as Psylla chinensis, Aphis citricola and Pseudococcus comstocki, while their incidence period was delayed to varying degrees, and the numbers of their dominant natural enemies (Coccinella septempunctata, Phytoseiulus persimilis and Chrysoperla sinica) increased. Intercropping with aromatic plants led to a considerable improvement in arthropod pest management by enhancing the activity of the beneficial arthropod community within the pear orchard ecosystem. Copyright © 2011 Society of Chemical Industry.

Water Resources Implications of Cellulosic Biofuel Production at a Regional Scale

NASA Astrophysics Data System (ADS)

Christopher, S. F.; Schoenholtz, S. H.; Nettles, J. E.

2011-12-01

Recent increases in oil prices, a strong national interest in greater energy independence, and a concern for the role of fossil fuels in global climate change, have led to a dramatic expansion in use of alternative renewable energy sources in the U.S. The U.S. government has mandated production of 36 billion gallons of renewable fuels by 2022, of which 16 billion gallons are required to be cellulosic biofuels. Production of cellulosic biomass offers a promising alternative to corn-based systems because large-scale production of corn-based ethanol often requires irrigation and is associated with increased erosion, excess sediment export, and enhanced leaching of nitrogen and phosphorus. Although cultivation of switchgrass using standard agricultural practices is one option being considered for production of cellulosic biomass, intercropping cellulosic biofuel crops within managed forests could provide feedstock without primary land use change or the water quality impacts associated with annual crops. Catchlight Energy LLC is examining the feasibility and sustainability of intercropping switchgrass in loblolly pine plantations in the southeastern U.S. Ongoing research is determining efficient operational techniques and information needed to evaluate effects of these practices on water resources in small watershed-scale (~25 ha) studies. Three sets of four to five sub-watersheds are fully instrumented and currently collecting calibration data in North Carolina, Alabama, and Mississippi. These watershed studies will provide detailed information to understand processes and guide management decisions. However, environmental implications of cellulosic systems need to be examined at a regional scale. We used the Soil Water Assessment Tool (SWAT), a physically-based hydrologic model, to examine water quantity effects of various land use change scenarios ranging from switchgrass intercropping a small percentage of managed pine forest land to conversion of all managed forested land to switchgrass. The regional-scale SWAT model was successfully run and calibrated on the ~ 5 million ha Tombigbee Watershed located in Mississippi and Alabama. Publically available datasets were used as input to the model and for calibration. To improve calibration statistics, five tree age classes (0-4 yr, 4-10 yr, 10-17 yr, 17-24 yr, 24-30 yr) were added to the model to more appropriately represent existing forested systems in the region, which are not included within the standard SWAT set-up. Our results will be essential to public policy makers as they influence and plan for large-scale production of cellulosic biofuels, while sustaining water quality and quantity.

[Effects of intercropping Chinese milk vetch on functional characteristics of soil microbial community in rape rhizosphere].

PubMed

Zhou, Quan; Wang, Long Chang; Xing, Yi; Ma, Shu Min; Zhang, Xiao Duan; Chen, Jiao; Shi, Chao

2018-03-01

The application of green manure is facing serious problems in purple soil region of southwest China. With the aim to explore the potential application of green manure, we examined the functional characteristics of soil microbial community in a system of Chinese milk vetch intercropped with rape. The innovations are the application of Chinese milk vetch in dry land of the southwest China and the establishment of new planting pattern of rape by providing empirical data. Results showed that the intercropping with Chinese milk vetch decreased the carbon resource use efficiency of microbial community in rape rhizosphere, especially for the utilization of carbohydrates. At the same time, Shannon index, Simpson index, and richness were reduced, but evenness index was increased by intercropping. Those results from cluster analysis and principal component analysis suggest that the soil microbial community composition was significantly different between monocropping and intercropping. The carbohydrates, amino acids and carboxylic acids were the sensitive carbon sources for differentiating the changes of the microbial community induced by monocropping and intercropping. Intercropping Chinese milk vetch could decrease functional activity, change community composition, and reduce diversity of soil microbial community in rape rhizosphere.

Integrated double mulching practices optimizes soil temperature and improves soil water utilization in arid environments

NASA Astrophysics Data System (ADS)

Yin, Wen; Feng, Fuxue; Zhao, Cai; Yu, Aizhong; Hu, Falong; Chai, Qiang; Gan, Yantai; Guo, Yao

2016-09-01

Water shortage threatens agricultural sustainability in many arid and semiarid areas of the world. It is unknown whether improved water conservation practices can be developed to alleviate this issue while increasing crop productivity. In this study, we developed a "double mulching" system, i.e., plastic film coupled with straw mulch, integrated together with intensified strip intercropping. We determined (i) the responses of soil evaporation and moisture conservation to the integrated double mulching system and (ii) the change of soil temperature during key plant growth stages under the integrated systems. Experiments were carried out in northwest China in 2009 to 2011. Results show that wheat-maize strip intercropping in combination with plastic film and straw covering on the soil surface increased soil moisture (mm) by an average of 3.8 % before sowing, 5.3 % during the wheat and maize co-growth period, 4.4 % after wheat harvest, and 4.9 % after maize harvest, compared to conventional practice (control). The double mulching decreased total evapotranspiration of the two intercrops by an average of 4.6 % ( P < 0.05), compared to control. An added feature was that the double mulching system decreased soil temperature in the top 10-cm depth by 1.26 to 1.31 °C in the strips of the cool-season wheat, and by 1.31 to 1.51 °C in the strips of the warm-season maize through the 2 years. Soil temperature of maize strips higher as 1.25 to 1.94 °C than that of wheat strips in the top 10-cm soil depth under intercropping with the double mulching system; especially higher as 1.58 to 2.11 °C under intercropping with the conventional tillage; this allows the two intercrops to grow in a well "collaborative" status under the double mulching system during their co-growth period. The improvement of soil moisture and the optimization of soil temperature for the two intercrops allow us to conclude that wheat-maize intensification with the double mulching system can be used as an effective farming model in alleviating water shortage issues experiencing in water shortage areas.

Acacia Changes Microbial Indicators and Increases C and N in Soil Organic Fractions in Intercropped Eucalyptus Plantations.

PubMed

Pereira, Arthur P A; Zagatto, Maurício R G; Brandani, Carolina B; Mescolotti, Denise de Lourdes; Cotta, Simone R; Gonçalves, José L M; Cardoso, Elke J B N

2018-01-01

Intercropping forest plantations of Eucalyptus with nitrogen-fixing trees can increase soil N inputs and stimulate soil organic matter (OM) cycling. However, microbial indicators and their correlation in specific fractions of soil OM are unclear in the tropical sandy soils. Here, we examined the microbial indicators associated with C and N in the soil resulting from pure and intercropped Eucalyptus grandis and Acacia mangium plantations. We hypothesized that introduction of A. mangium in a Eucalyptus plantation promotes changes in microbial indicators and increases C and N concentrations on labile fractions of the soil OM, when compared to pure eucalyptus plantations. We determined the microbial and enzymatic activity, and the potential for C degradation by the soil microbial community. Additionally, we evaluated soil OM fractions and litter parameters. Soil (0-20 cm) and litter samples were collected at 27 and 39 months after planting from the following treatments: pure E. grandis (E) and A. mangium (A) plantations, pure E. grandis plantations with N fertilizer (E+N) and an E. grandis , and A. mangium intercropped plantations (E+A). The results showed that intercropped plantations (E+A) increase 3, 45, and 70% microbial biomass C as compared to A, E+N, and E, at 27 months after planting. The metabolic quotient ( q CO 2 ) showed a tendency toward stressful values in pure E. grandis plantations and a strong correlation with dehydrogenase activity. A and E+A treatments also exhibited the highest organic fractions (OF) and C and N contents. A canonical redundancy analysis revealed positive correlations between microbial indicators of soil and litter attributes, and a strong effect of C and N variables in differentiating A and E+A from E and E+N treatments. The results suggested that a significant role of A. mangium enhance the dynamics of soil microbial indicators which help in the accumulation of C and N in soil OF in intercropped E. grandis plantations. Our results are mostly relevant to plantations in sandy soil areas with low levels of OM, suggesting and efficient method for improving nutrient availability in the soil and optimizing eucalyptus growth and development.

Acacia Changes Microbial Indicators and Increases C and N in Soil Organic Fractions in Intercropped Eucalyptus Plantations

PubMed Central

Pereira, Arthur P. A.; Zagatto, Maurício R. G.; Brandani, Carolina B.; Mescolotti, Denise de Lourdes; Cotta, Simone R.; Gonçalves, José L. M.; Cardoso, Elke J. B. N.

2018-01-01

Intercropping forest plantations of Eucalyptus with nitrogen-fixing trees can increase soil N inputs and stimulate soil organic matter (OM) cycling. However, microbial indicators and their correlation in specific fractions of soil OM are unclear in the tropical sandy soils. Here, we examined the microbial indicators associated with C and N in the soil resulting from pure and intercropped Eucalyptus grandis and Acacia mangium plantations. We hypothesized that introduction of A. mangium in a Eucalyptus plantation promotes changes in microbial indicators and increases C and N concentrations on labile fractions of the soil OM, when compared to pure eucalyptus plantations. We determined the microbial and enzymatic activity, and the potential for C degradation by the soil microbial community. Additionally, we evaluated soil OM fractions and litter parameters. Soil (0–20 cm) and litter samples were collected at 27 and 39 months after planting from the following treatments: pure E. grandis (E) and A. mangium (A) plantations, pure E. grandis plantations with N fertilizer (E+N) and an E. grandis, and A. mangium intercropped plantations (E+A). The results showed that intercropped plantations (E+A) increase 3, 45, and 70% microbial biomass C as compared to A, E+N, and E, at 27 months after planting. The metabolic quotient (qCO2) showed a tendency toward stressful values in pure E. grandis plantations and a strong correlation with dehydrogenase activity. A and E+A treatments also exhibited the highest organic fractions (OF) and C and N contents. A canonical redundancy analysis revealed positive correlations between microbial indicators of soil and litter attributes, and a strong effect of C and N variables in differentiating A and E+A from E and E+N treatments. The results suggested that a significant role of A. mangium enhance the dynamics of soil microbial indicators which help in the accumulation of C and N in soil OF in intercropped E. grandis plantations. Our results are mostly relevant to plantations in sandy soil areas with low levels of OM, suggesting and efficient method for improving nutrient availability in the soil and optimizing eucalyptus growth and development. PMID:29670606

Belowground Interactions Impact the Soil Bacterial Community, Soil Fertility, and Crop Yield in Maize/Peanut Intercropping Systems

PubMed Central

Li, Qisong; Chen, Jun; Wu, Linkun; Luo, Xiaomian; Li, Na; Arafat, Yasir; Lin, Sheng; Lin, Wenxiong

2018-01-01

Intercropping has been widely used to control disease and improve yield in agriculture. In this study, maize and peanut were used for non-separation intercropping (NS), semi-separation intercropping (SS) using a nylon net, and complete separation intercropping (CS) using a plastic sheet. In field experiments, two-year land equivalent ratios (LERs) showed yield advantages due to belowground interactions when using NS and SS patterns as compared to monoculture. In contrast, intercropping without belowground interactions (CS) showed a yield disadvantage. Meanwhile, in pot experiments, belowground interactions (found in NS and SS) improved levels of soil-available nutrients (nitrogen (N) and phosphorus (P)) and enzymes (urease and acid phosphomonoesterase) as compared to intercropping without belowground interactions (CS). Soil bacterial community assay showed that soil bacterial communities in the NS and SS crops clustered together and were considerably different from the CS crops. The diversity of bacterial communities was significantly improved in soils with NS and SS. The abundance of beneficial bacteria, which have the functions of P-solubilization, pathogen suppression, and N-cycling, was improved in maize and peanut soils due to belowground interactions through intercropping. Among these bacteria, numbers of Bacillus, Brevibacillus brevis, and Paenibacillus were mainly increased in the maize rhizosphere. Burkholderia, Pseudomonas, and Rhizobium were mainly increased in the peanut rhizosphere. In conclusion, using maize and peanut intercropping, belowground interactions increased the numbers of beneficial bacteria in the soil and improved the diversity of the bacterial community, which was conducive to improving soil nutrient (N and P) supply capacity and soil microecosystem stability. PMID:29470429

Remediation of Arsenic contaminated soil using malposed intercropping of Pteris vittata L. and maize.

PubMed

Ma, Jie; Lei, En; Lei, Mei; Liu, Yanhong; Chen, Tongbin

2018-03-01

Intercropping of arsenic (As) hyperaccumulator and cash crops during remediation of contaminated soil has been applied in farmland remediation project. However, little is known about the fate of As fractions in the soil profile and As uptake within the intercropping plants under field condition. In this study, As removal, uptake, and translocation were investigated within an intercropping system of Pteris vittata L. (P. vittata) and maize (Zea mays). Results indicated that the concentration of As associated with amorphous Fe (hydr)oxides in the 10-20 cm soil layer was significantly lower under malposed intercropping of P. vittata and maize, and As accumulation in P. vittata and biomass of P. vittata were simultaneously higher under malposed intercropping than under coordinate intercropping, leading to a 2.4 times higher rate of As removal. Although maize roots absorbed over 13.4 mg kg -1 As and maize leaves and flowers accumulated over 21.5 mg kg -1 As (translocation factor higher than 1), grains produced in all intercropping modes accumulated lower levels of As, satisfying the standard for human consumption. Our results suggested that malposed intercropping of a hyperaccumulator and a low-accumulation cash crop was an ideal planting pattern for As remediation in soil. Furthermore, timely harvest of P. vittata, agronomic strategies during remediation, and appropriate management of the above ground parts of P. vittata and high-As tissues of cash crops may further improve remediation efficiency. Copyright © 2017. Published by Elsevier Ltd.

The influence of crop management on banana weevil, Cosmopolites sordidus (Coleoptera: Curculionidae) populations and yield of highland cooking banana (cv. Atwalira) in Uganda.

PubMed

Rukazambuga, N D T M; Gold, C S; Gowen, S R; Ragama, P

2002-10-01

A field study was undertaken in Uganda using highland cooking banana (cv. Atwalira) to test the hypothesis that bananas grown under stressed conditions are more susceptible to attack by Cosmopolites sordidus (Germar). Four banana treatments were employed to create different levels of host-plant vitality: (1) high stress: intercrop with finger millet; (2) moderate stress: monoculture without soil amendments; (3) low stress: monoculture with manure; (4) high vigour: monoculture with continuous mulch and manure. Adult C. sordidus were released at the base of banana mats 11 months after planting and populations were monitored for three years using mark and recapture methods. Cosmopolites sordidus density was greatest in the mulched plots which may have reflected increased longevity and/or longer tenure time in moist soils. Lowest C. sordidus numbers were found in intercropped banana. Damage, estimated as percentage corm tissue consumed by larvae, was similar among treatments. However, the total amount of tissue consumed was greater in mulched banana than in other systems. Plants supporting the heaviest levels of C. sordidus damage displayed bunch size reductions of 40-55%. Banana yield losses ranged from 14-20% per plot with similar levels in the intercropped and mulched systems. Yield reductions, reported as t ha-1, were twice as high in the mulched system as in the intercrop. The results from this study indicate that C. sordidus problems are not confined to stressed banana systems or those with low levels of management, but that the weevil can also attain pest status in well-managed and productive banana stands.

Effect of intercropping period management on runoff and erosion in a maize cropping system.

PubMed

Laloy, Eric; Bielders, C L

2010-01-01

The management of winter cover crops is likely to influence their performance in reducing runoff and erosion during the intercropping period that precedes spring crops but also during the subsequent spring crop. This study investigated the impact of two dates of destruction and burial of a rye (Secale cereale L.) and ryegrass (Lolium multiflorum Lam.) cover crop on runoff and erosion, focusing on a continuous silage maize (Zea mays L.) cropping system. Thirty erosion plots with various intercrop management options were monitored for 3 yr at two sites. During the intercropping period, cover crops reduced runoff and erosion by more than 94% compared with untilled, post-maize harvest plots. Rough tillage after maize harvest proved equally effective as a late sown cover crop. There was no effect of cover crop destruction and burial dates on runoff and erosion during the intercropping period, probably because rough tillage for cover crop burial compensates for the lack of soil cover. During two of the monitored maize seasons, it was observed that plots that had been covered during the previous intercropping period lost 40 to 90% less soil compared with maize plots that had been left bare during the intercropping period. The burial of an aboveground cover crop biomass in excess of 1.5 t ha(-1) was a necessary, yet not always sufficient, condition to induce a residual effect. Because of the possible beneficial residual effect of cover crop burial on erosion reduction, the sowing of a cover crop should be preferred over rough tillage after maize harvest.

An endophytic bacterium Acinetobacter calcoaceticus Sasm3-enhanced phytoremediation of nitrate-cadmium compound polluted soil by intercropping Sedum alfredii with oilseed rape.

PubMed

Chen, Bao; Ma, Xiaoxiao; Liu, Guiqing; Xu, Xiaomeng; Pan, Fengshan; Zhang, Jie; Tian, Shengke; Feng, Ying; Yang, Xiaoe

2015-11-01

Intensive agricultural system with high input of fertilizer results in high agricultural output. However, excessive fertilization in intensive agricultural system has great potential to cause nitrate and heavy metal accumulation in soil, which is adverse to human health. The main objective of the present study was to observe the effects of intercropping and inoculation of endophytic bacterium Acinetobacter calcoaceticus Sasm3 on phytoremediation of combined contaminated soil in oilseed rape (Brassica napus L.). The results showed that with Sasm3 inoculation, the biomass of rape was increased by 10-20% for shoot, 64% for root, and 23-29% for seeds while the nitrate accumulation in rape was decreased by 14% in root and by 12% in shoot. The cadmium concentration in rape increased significantly with mono-inoculating treatment, whereas it decreased significantly after intercropping treatment. By denaturing gradient gel electrophoresis (DGGE) and real-time quantitative PCR analysis, the diversity of bacterial community and the number of nirS and nirK gene copies increased significantly with inoculation or/and intercropping treatment. In conclusion, the endophytic bacterium Sasm3-inoculated intercropping system not only improved the efficiency of clearing cadmium from soil without obstructing crop production, but also improved the quality of crop.

Arbuscular mycorrhizal fungi and rhizobium facilitate nitrogen uptake and transfer in soybean/maize intercropping system

PubMed Central

Meng, Lingbo; Zhang, Aiyuan; Wang, Fei; Han, Xiaoguang; Wang, Dejiang; Li, Shumin

2015-01-01

The tripartite symbiosis between legumes, rhizobia and mycorrhizal fungi are generally considered to be beneficial for the nitrogen (N) uptake of legumes, but the facilitation of symbiosis in legume/non-legume intercropping systems is not clear. Therefore, the aims of the research are as follows: (1) to verify if the dual inoculation can facilitate the N uptake and N transfer in maize/soybean intercropping systems and (2) to calculate how much N will be transferred from soybean to maize. A pot experiment with different root separations [solid barrier, mesh (30 μm) barrier and no barrier] was conducted, and the 15N isotopic tracing method was used to calculate how much N transferred from soybean to maize inoculated with arbuscular mycorrhizal fungi (AMF) and rhizobium in a soybean (Glycine max L.cv. Dongnong No. 42)/maize (Zea mays L.cv. Dongnong No. 48) intercropping system. Compared with the Glomus mosseae inoculation (G.m.), Rhizobium SH212 inoculation (SH212), no inoculation (NI), the dual inoculation (SH212+G.m.) increased the N uptake of soybean by 28.69, 39.58, and 93.07% in a solid barrier system. N uptake of maize inoculated with both G. mosseae and rhizobium was 1.20, 1.28, and 1.68 times more than that of G.m., SH212 and NI, respectively, in solid barrier treatments. In addition, the amount of N transferred from soybean to maize in a dual inoculation system with a mesh barrier was 7.25, 7.01, and 11.45 mg more than that of G.m., SH212 and NI and similarly, 6.40, 7.58, and 12.46 mg increased in no barrier treatments. Inoculating with both AMF and rhizobium in the soybean/maize intercropping system improved the N fixation efficiency of soybean and promoted N transfer from soybean to maize, resulting in the improvement of yield advantages of legume/non-legume intercropping. PMID:26029236

Arbuscular mycorrhizal fungi and rhizobium facilitate nitrogen uptake and transfer in soybean/maize intercropping system.

PubMed

Meng, Lingbo; Zhang, Aiyuan; Wang, Fei; Han, Xiaoguang; Wang, Dejiang; Li, Shumin

2015-01-01

The tripartite symbiosis between legumes, rhizobia and mycorrhizal fungi are generally considered to be beneficial for the nitrogen (N) uptake of legumes, but the facilitation of symbiosis in legume/non-legume intercropping systems is not clear. Therefore, the aims of the research are as follows: (1) to verify if the dual inoculation can facilitate the N uptake and N transfer in maize/soybean intercropping systems and (2) to calculate how much N will be transferred from soybean to maize. A pot experiment with different root separations [solid barrier, mesh (30 μm) barrier and no barrier] was conducted, and the (15)N isotopic tracing method was used to calculate how much N transferred from soybean to maize inoculated with arbuscular mycorrhizal fungi (AMF) and rhizobium in a soybean (Glycine max L.cv. Dongnong No. 42)/maize (Zea mays L.cv. Dongnong No. 48) intercropping system. Compared with the Glomus mosseae inoculation (G.m.), Rhizobium SH212 inoculation (SH212), no inoculation (NI), the dual inoculation (SH212+G.m.) increased the N uptake of soybean by 28.69, 39.58, and 93.07% in a solid barrier system. N uptake of maize inoculated with both G. mosseae and rhizobium was 1.20, 1.28, and 1.68 times more than that of G.m., SH212 and NI, respectively, in solid barrier treatments. In addition, the amount of N transferred from soybean to maize in a dual inoculation system with a mesh barrier was 7.25, 7.01, and 11.45 mg more than that of G.m., SH212 and NI and similarly, 6.40, 7.58, and 12.46 mg increased in no barrier treatments. Inoculating with both AMF and rhizobium in the soybean/maize intercropping system improved the N fixation efficiency of soybean and promoted N transfer from soybean to maize, resulting in the improvement of yield advantages of legume/non-legume intercropping.

Allocation of Nitrogen and Carbon Is Regulated by Nodulation and Mycorrhizal Networks in Soybean/Maize Intercropping System

PubMed Central

Wang, Guihua; Sheng, Lichao; Zhao, Dan; Sheng, Jiandong; Wang, Xiurong; Liao, Hong

2016-01-01

Soybean/maize intercropping has remarkable advantages in increasing crop yield and nitrogen (N) efficiency. However, little is known about the contributions of rhizobia or arbuscular mycorrhizal fungi (AMF) to yield increases and N acquisition in the intercropping system. Plus, the mechanisms controlling carbon (C) and N allocation in intercropping systems remain unsettled. In the present study, a greenhouse experiment combined with 15N and 13C labeling was conducted using various inoculation and nutrient treatments. The results showed that co-inoculation with AMF and rhizobia dramatically increased biomass and N content of soybean and maize, and moderate application of N and phosphorus largely amplified the effect of co-inoculation. Maize had a competitive advantage over soybean only under co-inoculation and moderate nutrient availability conditions, indicating that the effects of AMF and rhizobia in intercropping systems are closely related to nutrient status. Results from 15N labeling showed that the amount of N transferred from soybean to maize in co-inoculations was 54% higher than that with AMF inoculation alone, with this increased N transfer partly resulting from symbiotic N fixation. The results from 13C labeling showed that 13C content increased in maize shoots and decreased in soybean roots with AMF inoculation compared to uninoculated controls. Yet, with co-inoculation, 13C content increased in soybean. These results indicate that photosynthate assimilation is stimulated by AM symbiosis in maize and rhizobial symbiosis in soybean, but AMF inoculation leads to soybean investing more carbon than maize into common mycorrhizal networks (CMNs). Overall, the results herein demonstrate that the growth advantage of maize when intercropped with soybean is due to acquisition of N by maize via CMNs while this crop contributes less C into CMNs than soybean under co-inoculation conditions. PMID:28018420

Allocation of Nitrogen and Carbon Is Regulated by Nodulation and Mycorrhizal Networks in Soybean/Maize Intercropping System.

PubMed

Wang, Guihua; Sheng, Lichao; Zhao, Dan; Sheng, Jiandong; Wang, Xiurong; Liao, Hong

2016-01-01

Soybean/maize intercropping has remarkable advantages in increasing crop yield and nitrogen (N) efficiency. However, little is known about the contributions of rhizobia or arbuscular mycorrhizal fungi (AMF) to yield increases and N acquisition in the intercropping system. Plus, the mechanisms controlling carbon (C) and N allocation in intercropping systems remain unsettled. In the present study, a greenhouse experiment combined with 15 N and 13 C labeling was conducted using various inoculation and nutrient treatments. The results showed that co-inoculation with AMF and rhizobia dramatically increased biomass and N content of soybean and maize, and moderate application of N and phosphorus largely amplified the effect of co-inoculation. Maize had a competitive advantage over soybean only under co-inoculation and moderate nutrient availability conditions, indicating that the effects of AMF and rhizobia in intercropping systems are closely related to nutrient status. Results from 15 N labeling showed that the amount of N transferred from soybean to maize in co-inoculations was 54% higher than that with AMF inoculation alone, with this increased N transfer partly resulting from symbiotic N fixation. The results from 13 C labeling showed that 13 C content increased in maize shoots and decreased in soybean roots with AMF inoculation compared to uninoculated controls. Yet, with co-inoculation, 13 C content increased in soybean. These results indicate that photosynthate assimilation is stimulated by AM symbiosis in maize and rhizobial symbiosis in soybean, but AMF inoculation leads to soybean investing more carbon than maize into common mycorrhizal networks (CMNs). Overall, the results herein demonstrate that the growth advantage of maize when intercropped with soybean is due to acquisition of N by maize via CMNs while this crop contributes less C into CMNs than soybean under co-inoculation conditions.

Synergy of agroforestry and bottomland hardwood afforestation

USGS Publications Warehouse

Twedt, D.J.; Portwood, J.; Clason, Terry R.

2003-01-01

Afforestation of bottomland hardwood forests has historically emphasized planting heavy-seeded tree species such as oak (Quercus spp.) and pecan (Caryaillinoensis) with little or no silvicultural management during stand development. Slow growth of these tree species, herbivory, competing vegetation, and limited seed dispersal, often result in restored sites that are slow to develop vertical vegetation structure and have limited tree diversity. Where soils and hydrology permit, agroforestry can provide transitional management that mitigates these historical limitations on converting cropland to forests. Planting short-rotation woody crops and intercropping using wide alleyways are two agroforestry practices that are well suited for transitional management. Weed control associated with agroforestry systems benefits planted trees by reducing competition. The resultant decrease in herbaceous cover suppresses small mammal populations and associated herbivory of trees and seeds. As a result, rapid vertical growth is possible that can 'train' under-planted, slower-growing, species and provide favorable environmental conditions for naturally invading trees. Finally, annual cropping of alleyways or rotational pulpwood harvest of woody crops provides income more rapidly than reliance on future revenue from traditional silviculture. Because of increased forest diversity, enhanced growth and development, and improved economic returns, we believe that using agroforestry as a transitional management strategy during afforestation provides greater benefits to landowners and to the environment than does traditional bottomland hardwood afforestation.

Intercropping Induces Changes in Specific Secondary Metabolite Concentration in Ethiopian Kale (Brassica carinata) and African Nightshade (Solanum scabrum) under Controlled Conditions.

PubMed

Ngwene, Benard; Neugart, Susanne; Baldermann, Susanne; Ravi, Beena; Schreiner, Monika

2017-01-01

Intercropping is widespread in small-holder farming systems in tropical regions and is also practiced in the cultivation of indigenous vegetables, to alleviate the multiple burdens of malnutrition. Due to interspecific competition and/or complementation between intercrops, intercropping may lead to changes in plants accumulation of minerals and secondary metabolites and hence, alter nutritional quality for consumers. Intercropping aims to intensify land productivity, while ensuring that nutritional quality is not compromised. This study aimed to investigate changes in minerals and secondary plant metabolites in intercropped Brassica carinata and Solanum scabrum , two important African indigenous vegetables, and evaluated the suitability of this combination for dryer areas. B. carinata and S. scabrum were grown for 6 weeks under controlled conditions in a greenhouse trial. Large rootboxes (8000 cm 3 volume) were specifically designed for this experiment. Each rootbox was planted with two plants, either of the same plant species (mono) or one of each plant species (mixed). A quartz sand/soil substrate was used and fertilized adequately for optimal plant growth. During the last 4 weeks of the experiment, the plants were either supplied with optimal (65% WHC) or low (30% WHC) irrigation, to test the effect of a late-season drought. Intercropping increased total glucosinolate content in B. carinata , while maintaining biomass production and the contents of other health related minerals in both B. carinata and S. scabrum . Moreover, low irrigation led to an increase in carotene accumulation in both mono and intercropped S. scabrum , but not in B. carinata , while the majority of kaempferol glycosides and hydroxycinnamic acid derivatives of both species were decreased by intercropping and drought treatment. This study indicates that some health-related phytochemicals can be modified by intercropping or late-season drought, but field validation of these results is necessary before definite recommendation can be made to stakeholders.

Gas exchange and stand-level estimates of water use and gross primary productivity in an experimental pine and switchgrass intercrop forestry system on the Lower Coastal Plain of North Carolina, U.S.A

Treesearch

Janine M. Albaugha; Jean-Christophe Domeca; Chris A. Maier; Eric B. Sucre; Zakiya H. Leggett; John S. King

2014-01-01

Despite growing interest in using switchgrass (Panicum virgatum L.) as a biofuel, there are limiteddata on the physiology of this species and its effect on stand water use and carbon (C) assimilationwhen grown as a forest intercrop for bioenergy. Therefore, we quantified gas exchange rates of switch-grass within intercropped plots and in pure switchgrass plots during...

Integrated double mulching practices optimizes soil temperature and improves soil water utilization in arid environments.

PubMed

Yin, Wen; Feng, Fuxue; Zhao, Cai; Yu, Aizhong; Hu, Falong; Chai, Qiang; Gan, Yantai; Guo, Yao

2016-09-01

Water shortage threatens agricultural sustainability in many arid and semiarid areas of the world. It is unknown whether improved water conservation practices can be developed to alleviate this issue while increasing crop productivity. In this study, we developed a "double mulching" system, i.e., plastic film coupled with straw mulch, integrated together with intensified strip intercropping. We determined (i) the responses of soil evaporation and moisture conservation to the integrated double mulching system and (ii) the change of soil temperature during key plant growth stages under the integrated systems. Experiments were carried out in northwest China in 2009 to 2011. Results show that wheat-maize strip intercropping in combination with plastic film and straw covering on the soil surface increased soil moisture (mm) by an average of 3.8 % before sowing, 5.3 % during the wheat and maize co-growth period, 4.4 % after wheat harvest, and 4.9 % after maize harvest, compared to conventional practice (control). The double mulching decreased total evapotranspiration of the two intercrops by an average of 4.6 % (P < 0.05), compared to control. An added feature was that the double mulching system decreased soil temperature in the top 10-cm depth by 1.26 to 1.31 °C in the strips of the cool-season wheat, and by 1.31 to 1.51 °C in the strips of the warm-season maize through the 2 years. Soil temperature of maize strips higher as 1.25 to 1.94 °C than that of wheat strips in the top 10-cm soil depth under intercropping with the double mulching system; especially higher as 1.58 to 2.11 °C under intercropping with the conventional tillage; this allows the two intercrops to grow in a well "collaborative" status under the double mulching system during their co-growth period. The improvement of soil moisture and the optimization of soil temperature for the two intercrops allow us to conclude that wheat-maize intensification with the double mulching system can be used as an effective farming model in alleviating water shortage issues experiencing in water shortage areas.

The Dynamic Process of Interspecific Interactions of Competitive Nitrogen Capture between Intercropped Wheat (Triticum aestivum L.) and Faba Bean (Vicia faba L.)

PubMed Central

2014-01-01

Wheat (Triticum aestivum L.)/faba bean (Vicia faba L.) intercropping shows significant overyielding and high nitrogen (N)-use efficiency, but the dynamics of plant interactions have rarely been estimated. The objective of the present study was to investigate the temporal dynamics of competitive N acquisition between intercropped wheat and faba bean with the logistic model. Wheat and faba bean were grown together or alone with limited N supply in pots. Data of shoot and root biomass and N content measured from 14 samplings were fitted to logistic models to determine instantaneous rates of growth and N uptake. The superiority of instantaneous biomass production and N uptake shifted from faba bean to wheat with their growth. Moreover, the shift of superiority on N uptake occurred 7–12 days earlier than that of biomass production. Interspecific competition stimulated intercropped wheat to have a much earlier and stronger superiority on instantaneous N uptake compared with isolated wheat. The modeling methodology characterized the temporal dynamics of biomass production and N uptake of intercropped wheat and faba bean in different planting systems, which helps to understand the underlying process of plant interaction for intercropping plants. PMID:25541699

The dynamic process of interspecific interactions of competitive nitrogen capture between intercropped wheat (Triticum aestivum L.) and Faba Bean (Vicia faba L.).

PubMed

Li, Chunjie; Dong, Yan; Li, Haigang; Shen, Jianbo; Zhang, Fusuo

2014-01-01

Wheat (Triticum aestivum L.)/faba bean (Vicia faba L.) intercropping shows significant overyielding and high nitrogen (N)-use efficiency, but the dynamics of plant interactions have rarely been estimated. The objective of the present study was to investigate the temporal dynamics of competitive N acquisition between intercropped wheat and faba bean with the logistic model. Wheat and faba bean were grown together or alone with limited N supply in pots. Data of shoot and root biomass and N content measured from 14 samplings were fitted to logistic models to determine instantaneous rates of growth and N uptake. The superiority of instantaneous biomass production and N uptake shifted from faba bean to wheat with their growth. Moreover, the shift of superiority on N uptake occurred 7-12 days earlier than that of biomass production. Interspecific competition stimulated intercropped wheat to have a much earlier and stronger superiority on instantaneous N uptake compared with isolated wheat. The modeling methodology characterized the temporal dynamics of biomass production and N uptake of intercropped wheat and faba bean in different planting systems, which helps to understand the underlying process of plant interaction for intercropping plants.

Root Interactions in a Maize/Soybean Intercropping System Control Soybean Soil-Borne Disease, Red Crown Rot

PubMed Central

Gao, Xiang; Wu, Man; Xu, Ruineng; Wang, Xiurong; Pan, Ruqian; Kim, Hye-Ji; Liao, Hong

2014-01-01

Background Within-field multiple crop species intercropping is well documented and used for disease control, but the underlying mechanisms are still unclear. As roots are the primary organ for perceiving signals in the soil from neighboring plants, root behavior may play an important role in soil-borne disease control. Principal Findings In two years of field experiments, maize/soybean intercropping suppressed the occurrence of soybean red crown rot, a severe soil-borne disease caused by Cylindrocladium parasiticum (C. parasiticum). The suppressive effects decreased with increasing distance between intercropped plants under both low P and high P supply, suggesting that root interactions play a significant role independent of nutrient status. Further detailed quantitative studies revealed that the diversity and intensity of root interactions altered the expression of important soybean PR genes, as well as, the activity of corresponding enzymes in both P treatments. Furthermore, 5 phenolic acids were detected in root exudates of maize/soybean intercropped plants. Among these phenolic acids, cinnamic acid was released in significantly greater concentrations when intercropped maize with soybean compared to either crop grown in monoculture, and this spike in cinnamic acid was found dramatically constrain C. parasiticum growth in vitro. Conclusions To the best of our knowledge, this study is the first report to demonstrate that intercropping with maize can promote resistance in soybean to red crown rot in a root-dependent manner. This supports the point that intercropping may be an efficient ecological strategy to control soil-borne plant disease and should be incorporated in sustainable agricultural management practices. PMID:24810161

Increased soil organic carbon stocks under agroforestry: A survey of six different sites in France

NASA Astrophysics Data System (ADS)

Cardinael, Rémi; Chevallier, Tiphaine; Cambou, Aurélie; Beral, Camille; Barthes, Bernard; Dupraz, Christian; Kouakoua, Ernest; Chenu, Claire

2017-04-01

Introduction: Agroforestry systems are land use management systems in which trees are grown in combination with crops or pasture in the same field. In silvoarable systems, trees are intercropped with arable crops, and in silvopastoral systems trees are combined with pasture for livestock. These systems may produce forage and timber as well as providing ecosystem services such as climate change mitigation. Carbon (C) is stored in the aboveground and belowground biomass of the trees, and the transfer of organic matter from the trees to the soil can increase soil organic carbon (SOC) stocks. Few studies have assessed the impact of agroforestry systems on carbon storage in soils in temperate climates, as most have been undertaken in tropical regions. Methods: This study assessed five silvoarable systems and one silvopastoral system in France. All sites had an agroforestry system with an adjacent, purely agricultural control plot. The land use management in the inter-rows in the agroforestry systems and in the control plots were identical. The age of the study sites ranged from 6 to 41 years after tree planting. Depending on the type of soil, the sampling depth ranged from 20 to 100 cm and SOC stocks were assessed using equivalent soil masses. The aboveground biomass of the trees was also measured at all sites. Results: In the silvoarable systems, the mean organic carbon stock accumulation rate in the soil was 0.24 (0.09-0.46) Mg C ha-1 yr-1 at a depth of 30 cm and 0.65 (0.004-1.85) Mg C ha-1 yr-1 in the tree biomass. Increased SOC stocks were also found in deeper soil layers at two silvoarable sites. Young plantations stored additional SOC but mainly in the soil under the rows of trees, possibly as a result of the herbaceous vegetation growing in the rows. At the silvopastoral site, the SOC stock was significantly greater at a depth of 30-50 cm than in the control. Overall, this study showed the potential of agroforestry systems to store C in both soil and biomass in temperate regions.

The influence of trees on the thermal environment and behaviour of grazing heifers in Brazilian Midwest.

PubMed

Lopes, Luciano Bastos; Eckstein, Camila; Pina, Douglas Santos; Carnevalli, Roberta Aparecida

2016-04-01

The intensification of the livestock production system has gained prominence over the last decades. In addition to the reduction of grazing areas and increased productivity per hectare, the intercropping involving forest tree species and ruminants has been established as a sustainable production model, generating income and valuation of natural capital. Besides the social, economic, and environmental aspects, the animal welfare is a noteworthy factor. The objective of this study was to evaluate the microclimatic conditions in an open-pasture and in silvopastoral systems, considering the Temperature Humidity Index (THI) and alterations in animal behavior. Three different pasture arrangements were analyzed in this study: total absence of trees in an open-pasture (ArrA), presence of peripheral trees (Eucalyptus spp.) along the border fences (ArrB), and an intensive wooded area aggregated with pasture (ArrC). A herd of 24 crossbreed heifers (3/4 and 7/8 Holstein-Girolando breed) was evaluated. Behavior data were collected every 15 min starting at 08 h00 with readings ending at 16 h00. THI was used to evaluate the environmental comfort. The THI found in the system with open-pasture and in the two systems with silvopastoral arrangement reached critical levels. The two arrangements with eucalyptus rows were not capable of eliminating heat stress in the conditions found in the north region of Mato Grosso State although better conditions were obtained under the tree canopy. The differences between the microclimatic variables for the three arrangements modified the behavior of the animals regarding their location and activity, except for water consumption.

Modeling large-scale adoption of intercropping as a sustainable agricultural practice for food security and air pollution mitigation around the globe

NASA Astrophysics Data System (ADS)

Fung, K. M.; Tai, A. P. K.; Yong, T.; Liu, X.

2017-12-01

The fast-growing world population will impose a severe pressure on our current global food production system. Meanwhile, boosting crop yield by increasing fertilizer use comes with a cascade of environmental problems including air pollution. In China, agricultural activities contribute to 95% of total ammonia emissions. Such emissions are attributable to 20% of the fine particulate matter (PM2.5) formed in the downwind regions, which imposes severe health risks to the citizens. Field studies of soybean intercropping have demonstrated its potential to enhance crop yield, lower fertilizer use, and thus reduce ammonia emissions by taking advantage of legume nitrogen fixation and enabling mutualistic crop-crop interactions between legumes and non-legume crops. In our work, we revise the process-based biogeochemical model, DeNitrification-DeComposition (DNDC) to capture the belowground interactions of intercropped crops and show that with intercropping, only 58% of fertilizer is required to yield the same maize production of its monoculture counterpart, corresponding to a reduction in ammonia emission by 43% over China. Using the GEOS-Chem global 3-D chemical transport model, we estimate that such ammonia reduction can lessen downwind inorganic PM2.5 by up to 2.1% (equivalent to 1.3 μg m-3), which saves the Chinese air pollution-related health costs by up to US$1.5 billion each year. With the more enhanced crop growth and land management algorithms in the Community Land Model (CLM), we also implement into CLM the new parametrization of the belowground interactions to simulate large-scale adoption of intercropping around the globe and study their beneficial effects on food production, fertilizer usage and ammonia reduction. This study can serve as a scientific basis for policy makers and intergovernmental organizations to consider promoting large-scale intercropping to maintain a sustainable global food supply to secure both future crop production and air quality.

Evaluation of vegetable-faba bean (Vicia faba L.) intercropping under Latvian agro-ecological conditions.

PubMed

Lepse, Līga; Dane, Sandra; Zeipiņa, Solvita; Domínguez-Perles, Raul; Rosa, Eduardo As

2017-10-01

Monoculture is used mostly in conventional agriculture, where a single crop is cultivated on the same land for a period of at least 12 months. In an organic and integrated growing approach, more attention is paid to plant-environment interactions and, as a result, diverse growing systems applying intercropping, catch crops, and green manure are being implemented. Thus, field experiments for evaluation of vegetable/faba bean full intercropping efficiency, in terms of vegetable and faba bean yield and protein content, were set up during two consecutive growing seasons (2014 and 2015). Data obtained showed that the most efficient intercropping variants were cabbage/faba bean (cabbage yield 1.27-2.91 kg m -2 , immature faba bean pods 0.20-0.43 kg m -2 ) and carrot/faba bean (carrot yield 1.67-2.28 kg m -2 , immature faba bean pods 0.10-0.52 kg m -2 ), whilst onion and faba bean intercrop is not recommended for vegetable growing since it induces a very low onion yield (0.66-1.09 kg m -2 ), although the highest immature faba bean pod yield was found in the onion/faba bean intercropping scheme (up to 0.56 kg m -2 ). Vegetable/faba bean intercropping can be used in practical horticulture for carrot and cabbage growing in order to ensure sustainable farming and environmentally friendly horticultural production. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Water Quality and Quantity Implications of Biofuel Intercropping at a Regional Scale (Invited)

NASA Astrophysics Data System (ADS)

Christopher, S. F.; Schoenholtz, S. H.; Nettles, J.

2010-12-01

Because of a strong national interest in greater energy independence and concern for the role of fossil fuels in global climate change, the importance of biofuels as an alternative renewable energy source has developed rapidly. The U.S. government has mandated production of 36 billion gallons of renewable fuels by 2022, which compromises 15 % of U.S. liquid transportation fuels. Large-scale production of corn-based ethanol often requires irrigation and is associated with erosion, excess sediment export, and leaching of nitrogen and phosphorus. Production of cellulosic biomass offers a promising alternative to corn-based systems. Although cultivation of switchgrass using standard agricultural practices is one option being considered for production of cellulosic biomass, intercropping cellulosic biofuel crops within managed forests could provide feedstock without primary land use change or the water quality impacts associated with annual crops. Catchlight Energy LLC is examining the feasibility and sustainability of intercropping switchgrass in loblolly pine plantations in the southeastern US. While ongoing research is determining efficient operational techniques, information needed to evaluate the effects of these practices on water resources, such as field-scale evapotranspiration rates, nutrient cycling, and soil erosion rates are being examined in a large watershed study. Three sets of four to five sub-watersheds are fully instrumented and currently collecting calibration data, with forest-based biofuel treatments to be installed in 2011 and 2012. These watershed studies will give us detailed information to understand processes and guide management decisions. However, environmental implications of these systems need to be examined at a regional scale. We used the Soil Water Assessment Tool (SWAT), a physically-based hydrologic model, to examine various scenarios ranging from switchgrass intercropping a small percentage of managed pine forest land to conversion of all managed forested land to switchgrass. The current results are based on early indicators from operational trials, but will be refined as the watershed studies progress. Our results will be essential to public policy makers as they influence and plan for large-scale production of cellulosic biofuels while sustaining water quality and quantity.

Soil Chemical Property Changes in Eggplant/Garlic Relay Intercropping Systems under Continuous Cropping

PubMed Central

Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen; Zhang, Mengru; Zhang, Hongjing

2014-01-01

Soil sickness is a critical problem for eggplant (Solanum melongena L.) under continuous cropping that affects sustainable eggplant production. Relay intercropping is a significant technique on promoting soil quality, improving eco-environment, and raising output. Field experiments were conducted from September 2010 to November 2012 in northwest China to determine the effects of relay intercropping eggplant with garlic (Allium sativum L.) on soil enzyme activities, available nutrient contents, and pH value under a plastic tunnel. Three treatments were in triplicate using randomized block design: eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). The major results are as follows: (1) the activities of soil invertase, urease, and alkaline phosphatase were generally enhanced in NG and GG treatments; (2) relay intercropping significantly increased the soil available nutrient contents, and they were mostly higher in GG than NG. On April 11, 2011, the eggplant/garlic co-growth stage, the available nitrogen content in GG was 76.30 mg·kg−1, significantly higher than 61.95 mg·kg−1 in NG. For available potassium on April 17, 2012, they were 398.48 and 387.97 mg·kg−1 in NG and GG, both were significantly higher than 314.84 mg·kg−1 in CK; (3) the soil pH showed a significantly higher level in NG treatment, but lower in GG treatment compared with CK. For the last samples in 2012, soil pH in NG and GG were 7.70 and 7.46, the highest and lowest one among them; (4) the alkaline phosphatase activity and pH displayed a similar decreasing trend with continuous cropping. These findings indicate that relay intercropping eggplant with garlic could be an ideal farming system to effectively improve soil nutrient content, increase soil fertility, and alleviate soil sickness to some extent. These findings are important in helping to develop sustainable eggplant production. PMID:25340875

Soil chemical property changes in eggplant/garlic relay intercropping systems under continuous cropping.

PubMed

Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen; Zhang, Mengru; Zhang, Hongjing

2014-01-01

Soil sickness is a critical problem for eggplant (Solanum melongena L.) under continuous cropping that affects sustainable eggplant production. Relay intercropping is a significant technique on promoting soil quality, improving eco-environment, and raising output. Field experiments were conducted from September 2010 to November 2012 in northwest China to determine the effects of relay intercropping eggplant with garlic (Allium sativum L.) on soil enzyme activities, available nutrient contents, and pH value under a plastic tunnel. Three treatments were in triplicate using randomized block design: eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). The major results are as follows: (1) the activities of soil invertase, urease, and alkaline phosphatase were generally enhanced in NG and GG treatments; (2) relay intercropping significantly increased the soil available nutrient contents, and they were mostly higher in GG than NG. On April 11, 2011, the eggplant/garlic co-growth stage, the available nitrogen content in GG was 76.30 mg·kg(-1), significantly higher than 61.95 mg·kg(-1) in NG. For available potassium on April 17, 2012, they were 398.48 and 387.97 mg·kg(-1) in NG and GG, both were significantly higher than 314.84 mg·kg(-1) in CK; (3) the soil pH showed a significantly higher level in NG treatment, but lower in GG treatment compared with CK. For the last samples in 2012, soil pH in NG and GG were 7.70 and 7.46, the highest and lowest one among them; (4) the alkaline phosphatase activity and pH displayed a similar decreasing trend with continuous cropping. These findings indicate that relay intercropping eggplant with garlic could be an ideal farming system to effectively improve soil nutrient content, increase soil fertility, and alleviate soil sickness to some extent. These findings are important in helping to develop sustainable eggplant production.

Weed Dynamics during Transition to Conservation Agriculture in Western Kenya Maize Production

PubMed Central

Odhiambo, Judith A.; Norton, Urszula; Ashilenje, Dennis; Omondi, Emmanuel C.; Norton, Jay B.

2015-01-01

Weed competition is a significant problem in maize (Zea mays, L.) production in Sub-Saharan Africa. Better understanding of weed management and costs in maize intercropped with beans (Phaseolus vulgaris, L.) during transition to conservation agricultural systems is needed. Changes in weed population and maize growth were assessed for a period of three years at Bungoma where crops are grown twice per year and at Trans-Nzoia where crops are grown once per year. Treatments included three tillage practices: minimum (MT), no-till (NT) and conventional (CT) applied to three cropping systems: continuous maize/bean intercropping (TYPICAL), maize/bean intercropping with relayed mucuna after bean harvest (RELAY) and maize, bean and mucuna planted in a strip intercropping arrangement (STRIP). Herbicides were used in NT, shallow hand hoeing and herbicides were used in MT and deep hoeing with no herbicides were used in CT. Weed and maize performance in the maize phase of each cropping system were assessed at both locations and costs of weed control were estimated at Manor House only. Weed density of grass and forb species declined significantly under MT and NT at Manor House and of grass species only at Mabanga. The greatest declines of more than 50% were observed as early as within one year of the transition to MT and NT in STRIP and TYPICAL cropping systems at Manor House. Transitioning to conservation based systems resulted in a decline of four out of five most dominant weed species. At the same time, no negative impact of MT or NT on maize growth was observed. Corresponding costs of weed management were reduced by $148.40 ha-1 in MT and $149.60 ha-1 in NT compared with CT. In conclusion, farmers can benefit from effective and less expensive weed management alternatives early in the process of transitioning to reduced tillage operations. PMID:26237404

Weed Dynamics during Transition to Conservation Agriculture in Western Kenya Maize Production.

PubMed

Odhiambo, Judith A; Norton, Urszula; Ashilenje, Dennis; Omondi, Emmanuel C; Norton, Jay B

2015-01-01

Weed competition is a significant problem in maize (Zea mays, L.) production in Sub-Saharan Africa. Better understanding of weed management and costs in maize intercropped with beans (Phaseolus vulgaris, L.) during transition to conservation agricultural systems is needed. Changes in weed population and maize growth were assessed for a period of three years at Bungoma where crops are grown twice per year and at Trans-Nzoia where crops are grown once per year. Treatments included three tillage practices: minimum (MT), no-till (NT) and conventional (CT) applied to three cropping systems: continuous maize/bean intercropping (TYPICAL), maize/bean intercropping with relayed mucuna after bean harvest (RELAY) and maize, bean and mucuna planted in a strip intercropping arrangement (STRIP). Herbicides were used in NT, shallow hand hoeing and herbicides were used in MT and deep hoeing with no herbicides were used in CT. Weed and maize performance in the maize phase of each cropping system were assessed at both locations and costs of weed control were estimated at Manor House only. Weed density of grass and forb species declined significantly under MT and NT at Manor House and of grass species only at Mabanga. The greatest declines of more than 50% were observed as early as within one year of the transition to MT and NT in STRIP and TYPICAL cropping systems at Manor House. Transitioning to conservation based systems resulted in a decline of four out of five most dominant weed species. At the same time, no negative impact of MT or NT on maize growth was observed. Corresponding costs of weed management were reduced by $148.40 ha(-1) in MT and $149.60 ha(-1) in NT compared with CT. In conclusion, farmers can benefit from effective and less expensive weed management alternatives early in the process of transitioning to reduced tillage operations.

Association of Shifting Populations in the Root Zone Microbiome of Millet with Enhanced Crop Productivity in the Sahel Region (Africa)

PubMed Central

Assigbetse, Komi; Bayala, Roger; Chapuis-Lardy, Lydie; Dick, Richard P.; McSpadden Gardener, Brian B.

2015-01-01

This study characterized specific changes in the millet root zone microbiome stimulated by long-term woody-shrub intercropping at different sites in Senegal. At the two study sites, intercropping with woody shrubs and shrub residue resulted in a significant increase in millet [Pennisetum glaucum (L.) R. Br.] yield (P < 0.05) and associated patterns of increased diversity in both bacterial and fungal communities in the root zone of the crop. Across four experiments, operational taxonomic units (OTUs) belonging to Chitinophaga were consistently significantly (P < 0.001) enriched in the intercropped samples, and “Candidatus Koribacter” was consistently significantly enriched in samples where millet was grown alone. Those OTUs belonging to Chitinophaga were enriched more than 30-fold in residue-amended samples and formed a distinct subgroup from all OTUs detected in the genus. Additionally, OTUs belonging to 8 fungal genera (Aspergillus, Coniella, Epicoccum, Fusarium, Gibberella, Lasiodiplodia, Penicillium, and Phoma) were significantly (P < 0.005) enriched in all experiments at all sites in intercropped samples. The OTUs of four genera (Epicoccum, Fusarium, Gibberella, and Haematonectria) were consistently enriched at sites where millet was grown alone. Those enriched OTUs in intercropped samples showed consistently large-magnitude differences, ranging from 30- to 1,000-fold increases in abundance. Consistently enriched OTUs in intercropped samples in the genera Aspergillus, Fusarium, and Penicillium also formed phylogenetically distinct subgroups. These results suggest that the intercropping system used here can influence the recruitment of potentially beneficial microorganisms to the root zone of millet and aid subsistence farmers in producing higher-yielding crops. PMID:25681183

Environmental sustainability of intercropping switchgrass in a loblolly pine forest

Treesearch

George Chescheir; Francois Birgand; Mohamed Youssef; Jami Nettles; Devendra Amatya

2016-01-01

A multi-institutional watershed study has been conducted since 2010 to quantify the environmental sustainability of planting switchgrass (Panicum virgatum L.) between wide rows of loblolly pine (Pinus taeda L.). The hypothesized advantage of this intercropping system is the production of biofuel feedstock to provide additional...

Greenhouse gas fluxes and root productivity in a switchgrass and loblolly pine intercropping system for bioenergy production

Treesearch

Paliza Shrestha; John R. Seiler; Brian D. Strahm; Eric B. Sucre; Zakiya H. Leggett

2015-01-01

This study is part of a larger collaborative effort to determine the overall environmental sustainability of intercropping pine (Pinus taeda L.) and switchgrass (Panicum virgatum L.), both of which are promising feedstock for bioenergy production in the Lower Coastal Plain in North Carolina.

Effect of population density of lettuce intercropped with rocket on productivity and land-use efficiency

PubMed Central

2018-01-01

The objective of this study was to evaluate the influence of the spacing of lettuce rows on the production of a lettuce-rocket intercropping system over two growing seasons (11 August to 25 September 2011 and 12 January to 24 February 2012) in Jaboticabal, São Paulo, Brazil. We evaluated 11 treatments in each season: lettuce-rocket intercrops with five row spacings for the lettuce (0.20, 0.25, 0.30, 0.35 and 0.40 m) and the rocket planted midway between the lettuce rows, sole crops of lettuce at the same five row spacings and a sole crop of rocket. Fresh and dry masses of the lettuce and rocket and number of lettuce leaves per plant were highest with a lettuce row spacing of 0.40 m, but the productivities of the lettuce and rocket were higher with a lettuce row spacing of 0.20 m. The productivities and fresh and dry weights of the lettuce and rocket and the number of lettuce leaves per plant were highest in the sole crops, but the fresh and dry weights of the rocket were higher with intercropping. The land equivalent ratios were >1.0 in both seasons in all intercrops and were highest for the densest crop (1.41). Intercropping was therefore 41% more efficient than sole cropping for the production of lettuce and rocket. PMID:29698401

Effect of population density of lettuce intercropped with rocket on productivity and land-use efficiency.

PubMed

Nascimento, Camila Seno; Cecílio Filho, Arthur Bernardes; Mendoza-Cortez, Juan Waldir; Nascimento, Carolina Seno; Bezerra Neto, Francisco; Grangeiro, Leilson Costa

2018-01-01

The objective of this study was to evaluate the influence of the spacing of lettuce rows on the production of a lettuce-rocket intercropping system over two growing seasons (11 August to 25 September 2011 and 12 January to 24 February 2012) in Jaboticabal, São Paulo, Brazil. We evaluated 11 treatments in each season: lettuce-rocket intercrops with five row spacings for the lettuce (0.20, 0.25, 0.30, 0.35 and 0.40 m) and the rocket planted midway between the lettuce rows, sole crops of lettuce at the same five row spacings and a sole crop of rocket. Fresh and dry masses of the lettuce and rocket and number of lettuce leaves per plant were highest with a lettuce row spacing of 0.40 m, but the productivities of the lettuce and rocket were higher with a lettuce row spacing of 0.20 m. The productivities and fresh and dry weights of the lettuce and rocket and the number of lettuce leaves per plant were highest in the sole crops, but the fresh and dry weights of the rocket were higher with intercropping. The land equivalent ratios were >1.0 in both seasons in all intercrops and were highest for the densest crop (1.41). Intercropping was therefore 41% more efficient than sole cropping for the production of lettuce and rocket.

Functional diversity in summer annual grass and legume intercrops in the Northeastern United States

USDA-ARS?s Scientific Manuscript database

A warm-season annual intercropping experiment was conducted across the Northeastern United States with four trials in 2013 and five trials in 2014 with four crop species selected based on differences in stature and nitrogen acquisition traits: 1) pearl millet (Pennisetum glaucum L.); 2) sorghum suda...

Dry Matter Production, Nutrient Cycled and Removed, and Soil Fertility Changes in Yam-Based Cropping Systems with Herbaceous Legumes in the Guinea-Sudan Zone of Benin.

PubMed

Maliki, Raphiou; Sinsin, Brice; Floquet, Anne; Cornet, Denis; Malezieux, Eric; Vernier, Philippe

2016-01-01

Traditional yam-based cropping systems (shifting cultivation, slash-and-burn, and short fallow) often result in deforestation and soil nutrient depletion. The objective of this study was to determine the impact of yam-based systems with herbaceous legumes on dry matter (DM) production (tubers, shoots), nutrients removed and recycled, and the soil fertility changes. We compared smallholders' traditional systems (1-year fallow of Andropogon gayanus-yam rotation, maize-yam rotation) with yam-based systems integrated herbaceous legumes (Aeschynomene histrix/maize intercropping-yam rotation, Mucuna pruriens/maize intercropping-yam rotation). The experiment was conducted during the 2002 and 2004 cropping seasons with 32 farmers, eight in each site. For each of them, a randomized complete block design with four treatments and four replicates was carried out using a partial nested model with five factors: Year, Replicate, Farmer, Site, and Treatment. Analysis of variance (ANOVA) using the general linear model (GLM) procedure was applied to the dry matter (DM) production (tubers, shoots), nutrient contribution to the systems, and soil properties at depths 0-10 and 10-20 cm. DM removed and recycled, total N, P, and K recycled or removed, and soil chemical properties (SOM, N, P, K, and pH water) were significantly improved on yam-based systems with legumes in comparison with traditional systems.

Dry Matter Production, Nutrient Cycled and Removed, and Soil Fertility Changes in Yam-Based Cropping Systems with Herbaceous Legumes in the Guinea-Sudan Zone of Benin

PubMed Central

Sinsin, Brice; Floquet, Anne; Cornet, Denis; Malezieux, Eric; Vernier, Philippe

2016-01-01

Traditional yam-based cropping systems (shifting cultivation, slash-and-burn, and short fallow) often result in deforestation and soil nutrient depletion. The objective of this study was to determine the impact of yam-based systems with herbaceous legumes on dry matter (DM) production (tubers, shoots), nutrients removed and recycled, and the soil fertility changes. We compared smallholders' traditional systems (1-year fallow of Andropogon gayanus-yam rotation, maize-yam rotation) with yam-based systems integrated herbaceous legumes (Aeschynomene histrix/maize intercropping-yam rotation, Mucuna pruriens/maize intercropping-yam rotation). The experiment was conducted during the 2002 and 2004 cropping seasons with 32 farmers, eight in each site. For each of them, a randomized complete block design with four treatments and four replicates was carried out using a partial nested model with five factors: Year, Replicate, Farmer, Site, and Treatment. Analysis of variance (ANOVA) using the general linear model (GLM) procedure was applied to the dry matter (DM) production (tubers, shoots), nutrient contribution to the systems, and soil properties at depths 0–10 and 10–20 cm. DM removed and recycled, total N, P, and K recycled or removed, and soil chemical properties (SOM, N, P, K, and pH water) were significantly improved on yam-based systems with legumes in comparison with traditional systems. PMID:27446635

[Effects of different multiple cropping systems on paddy field weed community under long term paddy-upland rotation].

PubMed

Yang, Bin-Juan; Huang, Guo-Qin; Xu, Ning; Wang, Shu-Bin

2013-09-01

Based on a long term field experiment, this paper studied the effects of different multiple cropping systems on the weed community composition and species diversity under paddy-upland rotation. The multiple cropping rotation systems could significantly decrease weed density and inhibited weed growth. Among the rotation systems, the milk vetch-early rice-late maize --> milk vetchearly maize intercropped with early soybean-late rice (CCSR) had the lowest weed species dominance, which inhibited the dominant weeds and decreased their damage. Under different multiple cropping systems, the main weed community was all composed of Monochoia vaginalis, Echinochloa crusgalli, and Sagittaria pygmae, and the similarity of weed community was higher, with the highest similarity appeared in milk vetch-early rice-late maize intercropped with late soybean --> milk vetch-early maize-late rice (CSCR) and in CCSR. In sum, the multiple cropping rotations in paddy field could inhibit weeds to a certain extent, but attentions should be paid to the damage of some less important weeds.

Harvest time residues of pendimethalin and oxyfluorfen in vegetables and soil in sugarcane-based intercropping systems.

PubMed

Kaur, Navneet; Bhullar, Makhan S

2015-05-01

Terminal residues of pendimethalin and oxyfluorfen applied in autumn sugarcane- and vegetables-based intercropping systems were analyzed in peas (Pisum sativum), cabbage (Brassica oleracea), garlic (Allium sativum), gobhi sarson (Brassica napus), and raya (Brassica juncea). The study was conducted in winter season in 2010-2011 and in 2011-2012 at Ludhiana, India. Pendimethalin at 0.56 kg and 0.75 kg ha(-1) was applied immediately after sowing of gobhi sarson, raya, peas, garlic, and 2 days before transplanting of cabbage seedlings. Oxyfluorfen at 0.17 kg and 0.23 kg ha(-1) was applied immediately after sowing of peas and garlic and 2 days before transplanting of cabbage seedlings intercropped in autumn sugarcane. Representative samples of these vegetables were collected at 75, 90, 100, and 165 days after application of herbicides and analyzed by high-performance liquid chromatograph (HPLC) with diode array detector for residues. The residue level of pendimethalin and oxyfluorfen in mature vegetables was found to be below the limit of quantification which is 0.05 mg kg(-1) for both the herbicides. The soil samples were collected at 0, 7, 15, 30, 45, and 60 days after the application of their herbicides. The residues of herbicides in soil samples were found to be below the detectability limit of 0.05 mg kg(-1) after 60 days in case of pendimethalin and after 45 days in case of oxyfluorfen.

[Effect of soil preparation and fertilization on foliage and shoot growth of Ginkgo biloba and its medicine content].

PubMed

He, Binghui; Zhong, Zhangcheng

2004-06-01

The study showed that the efficiency of various treatments in improving the height growth of Ginkgo biloba was organic fertilizer plus intercropping > soil preparation by blasting plus intercropping > organic fertilizer > soil preparation by blasting > intercropping, and the height growth increased by 14.5%, 8.6%, 5.7%, 3.2% and 0, respectively. The efficiency of the treatments in improving new shoot growth was organic fertilizer plus intercropping > soil preparation by blasting plus intercropping > intercropping > organic fertilizer > soil preparation by blasting, and the new shoot growth increased by 58.1%, 36.6%, 33.1%, 30.2% and 14.0%, respectively. Soil preparation, organic fertilization and intercropping had no different effect on the number of long shoots, but their effect on the numbers of short shoots and leaves was significantly different. The most efficient treatment in improving the medicine content was organic fertilization plus intercropping. Compared with control, the content of quercetin and rutin in Ginkgo biloba leaves increased by 420% and 220%, respectively.

[Microbial and physiological mechanisms for alleviating fusarium wilt of faba bean in intercropping system.

PubMed

Dong, Yan; Dong, Kun; Yang, Zhi Xian; Zheng, Yi; Tang, Li

2016-06-01

A field trial was conducted to investigate effects of wheat and faba bean intercropping on incidence and index of fusarium wilt, amount of Fusarium oxysporum of faba bean, oxidase activity and membrane peroxidation of faba bean roots. Functional diversity of microbial community in rhizosphere soil of faba bean was analyzed by using Biolog microbial analysis system, contents of pheno-lic acids in faba bean rhizosphere soil were determined with high performance liquid chromatography (HPLC). Results showed that in comparison with that of monocropped faba bean, wheat and faba bean intercropping tended to reduce the incidence and disease index of faba bean. The fusarium wilt was significantly decreased by 15.8% and 22.8% during the peak infection and late infection stages, and the average well color development (AWCD value) was promoted obviously. The Shannon diversity (H) and richness (S) increased by 4.4% and 19.4% during the peak infection stage and 5.3% and 37.1% during the late infection stage, respectively. Principal component analysis demonstrated that intercropping significantly changed the rhizospheric microbial community composition. The amount of F. oxysporum in rhizosphere soil of intercropped faba bean was significantly decreased by 53.8% and 33.1%, respectively, during the peak infection and late infection stages, and contents of 4-hydroxy benzoic acid, vanillic acid, syringic acid, ferulic acid, benzoic acid and cinnamic acid also significantly decreased, peroxidase (POD), catalases (CAT) activities in roots of intercropped faba bean increased significantly by 20.0% and 31.3%, respectively during the peak infection stage and 38.5% and 66.7% respectively during the late infection stage, and the malondialdehyd (MDA) content decreased significantly by 36.3% and 46.3%, respectively during peak infection stage and late infection stage. It was concluded that wheat with faba bean intercropping could significantly promote the soil microbial activity and diversity, reduce the accumulation of phenolic allelochemicals and the amount of F. oxysporum in rhizosphere soil, increase the activities of CAT and POD, reduce MDA content in roots, and thus promote the resistance of faba bean to F. oxysporum infection.

Crop acquisition of phosphorus, iron and zinc from soil in cereal/legume intercropping systems: a critical review

PubMed Central

Xue, Yanfang; Xia, Haiyong; Christie, Peter; Zhang, Zheng; Li, Long; Tang, Caixian

2016-01-01

Background Phosphorus (P), iron (Fe) and zinc (Zn) are essential elements for plant growth and development, but their availability in soil is often limited. Intercropping contributes to increased P, Fe and Zn uptake and thereby increases yield and improves grain nutritional quality and ultimately human health. A better understanding of how intercropping leads to increased plant P, Fe and Zn availability will help to improve P-fertilizer-use efficiency and agronomic Fe and Zn biofortification. Scope This review synthesizes the literature on how intercropping of legumes with cereals increases acquisition of P, Fe and Zn from soil and recapitulates what is known about root-to-shoot nutrient translocation, plant-internal nutrient remobilization and allocation to grains. Conclusions Direct interspecific facilitation in intercropping involves below-ground processes in which cereals increase Fe and Zn bioavailability while companion legumes benefit. This has been demonstrated and verified using isotopic nutrient tracing and molecular analysis. The same methodological approaches and field studies should be used to explore direct interspecific P facilitation. Both niche complementarity and interspecific facilitation contribute to increased P acquisition in intercropping. Niche complementarity may also contribute to increased Fe and Zn acquisition, an aspect poorly understood. Interspecific mobilization and uptake facilitation of sparingly soluble P, Fe and Zn from soil, however, are not the only determinants of the concentrations of P, Fe and Zn in grains. Grain yield and nutrient translocation from roots to shoots further influence the concentrations of these nutrients in grains. PMID:26749590

Regulation of Population Densities of Heterodera cajani and Other Plant-Parasitic Nematodes by Crop Rotations on Vertisols, in Semi-Arid Tropical Production Systems in India

PubMed Central

Sharma, S. B.; Rego, T. J.; Mohiuddin, M.; Rao, V. N.

1996-01-01

The significance of double crop (intercrop and sequential crop), single crop (rainy season crop fallow from June to September), and rotations on densities of Heterodera cajani, Helicotylenchus retusus, and Rotylenchulus reniformis was studied on Vertisol (Typic Pellusterts) between 1987 and 1993. Cowpea (Vigna sinensis), mungbean (Phaseolus aureus), and pigeonpea (Cajanus cajan) greatly increased the population densities of H. cajani and suppressed the population densities of other plant-parasitic nematodes. Mean population densities of H. cajani were about 8 times lower in single crop systems than in double crop systems, with pigeonpea as a component intercrop. Plots planted to sorghum, safflower, and chickpea in the preceding year contained fewer H. cajani eggs and juveniles than did plots previously planted to pigeonpea, cowpea, or mungbean. Continuous cropping of sorghum in the rainy season and safflower in the post-rainy season markedly reduced the population density of H. cajani. Sorghum, safflower, and chickpea favored increased population densities of H. retusus. Adding cowpea to the system resulted in a significant increase in the densities of R. reniformis. Mean densities of total plant-parasitic nematodes were three times greater in double crop systems, with pigeonpea as a component intercrop than in single crop systems with rainy season fallow component. Cropping systems had a regulatory effect on the nematode populations and could be an effective nematode management tactic. Intercropping of sorghum with H. cajani tolerant pigeonpea could be effective in increasing the productivity of traditional production systems in H. cajani infested regions. PMID:19277141

[Faba bean fusarium wilt (Fusarium oxysporum )control and its mechanism in different wheat varieties and faba bean intercropping system].

PubMed

Dong, Yan; Dong, Kun; Zheng, Yi; Tang, Li; Yang, Zhi-Xian

2014-07-01

Field experiment and hydroponic culture were conducted to investigate effects of three wheat varieties (Yunmai 42, Yunmai 47 and Mianyang 29) and faba bean intercropping on the shoot biomass, disease index of fusarium wilt, functional diversity of microbial community and the amount of Fusarium oxysporum in rhizosphere of faba bean. Contents and components of the soluble sugars, free amino acids and organic acids in the root exudates were also examined. Results showed that, compared with monocropped faba bean, shoot biomass of faba bean significantly increased by 16.6% and 13.4%, disease index of faba bean fusarium wilt significantly decreased by 47.6% and 23.3% as intercropped with Yunmai 42 and Yunmai 47, but no significant differences of both shoot biomass and disease index were found as intercropped with Mianyang 29. Compared with monocropped faba bean, the average well color development (AWCD value) and total utilization ability of carbon sources of faba bean significantly increased, the amount of Fusarium oxysporum of faba bean rhizosphere significantly decreased, and the microbial community structures of faba bean rhizosphere changed as intercropped with YM42 and YM47, while no significant effects as intercropped with MY29. Total contents of soluble sugar, free amino acids and organic acids in root exudates were in the trend of MY29>YM47>YM42. Contents of serine, glutamic, glycine, valine, methionine, phenylalanine, lysine in root exudates of MY29 were significantly higher than that in YM42 and YM47. The arginine was detected only in the root exudates of YM42 and YM47, and leucine was detected only in the root exudates of MY29. Six organic acids of tartaric acid, malic acid, citric acid, succinic acid, fumaric acid, t-aconitic acid were detected in root exudates of MY29 and YM47, and four organic acids of tartaric acid, malic acid, citric acid, fumaric acid were detected in root exudates of YM42. Malic acid content in root exudates of YM47 and MY29 was significantly higher than that of YM42. In conclusion, intercropping influenced the microbial activity and substrate utilization of soil microorganisms, altered the microbial community diversity in rhizosphere of faba bean, reduced the amount of F. oxysporum and disease index of faba bean fusarium wilt, and promoted faba bean growth. Effects of intercropping on disease control were influenced by the intercropped wheat variety, suggesting that the differences of root exudates of wheat were important factors that affected soil-borne diseases control in intercropping.

Homestead tree planting in two rural Swazi communities

USGS Publications Warehouse

Allen, James A.

1990-01-01

Tree planting practices were investigated on a total of 95 homesteads in two communities in rural Swaziland. Information was also collected on socioeconomic characteristics of the homesteads. In both the study areas, Sigombeni and Bhekinkosi, there was considerable variation amongst individual homesteads in size, relative wealth (as indicated by cattle and motor vehicle ownership), and amount and types of trees planted. Eighty-five percent of all homesteads in Sigombeni and 73% in Bhekinkosi had planted at least one tree. Common forms of planting included small woodlots, fruit trees, and ornamentals. Virtually all the woodlots consisted of two introduced wattle species (Acacia mearnsii and A. decurrens). The most commonly planted fruit trees were avocados, bananas, and peaches. No complex or labor-intensive agroforestry practices (such as maize/leucaena intercropping) were observed. There was some evidence that the poorest and newest homesteads were the least likely to have planted any trees and that the richest homesteads were the most likely to have planted woodlots. The results indicate that forestry research and extension efforts should take into account homestead characteristics, and strive to offer a range of tree planting options that vary in input requirements, labor needs, and complexity.

Reduce pests, enhance production: benefits of intercropping at high densities for okra farmers in Cameroon.

PubMed

Singh, Akanksha; Weisser, Wolfgang W; Hanna, Rachid; Houmgny, Raissa; Zytynska, Sharon E

2017-10-01

Intercropping can help reduce insect pest populations. However, the results of intercropping can be pest- and crop-species specific, with varying effects on crop yield, and pest suppression success. In Cameroon, okra vegetable is often grown in intercropped fields and sown with large distances between planting rows (∼ 2 m). Dominant okra pests include cotton aphids, leaf beetles and whiteflies. In a field experiment, we intercropped okra with maize and bean in different combinations (okra monoculture, okra-bean, okra-maize and okra-bean-maize) and altered plant densities (high and low) to test for the effects of diversity, crop identity and planting distances on okra pests, their predators and yield. We found crop identity and plant density, but not crop diversity to influence okra pests, their predators and okra yield. Only leaf beetles decreased okra yield and their abundance reduced at high plant density. Overall, okra grown with bean at high density was the most economically profitable combination. We suggest that when okra is grown at higher densities, legumes (e.g. beans) should be included as an additional crop. Intercropping with a leguminous crop can enhance nitrogen in the soil, benefiting other crops, while also being harvested and sold at market for additional profit. Manipulating planting distances and selecting plants based on their beneficial traits may thus help to eliminate yield gaps in sustainable agriculture. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Long-term field phytoextraction of zinc/cadmium contaminated soil by Sedum plumbizincicola under different agronomic strategies.

PubMed

Deng, Lin; Li, Zhu; Wang, Jie; Liu, Hongyan; Li, Na; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Christie, Peter

2016-01-01

In two long-term field experiments the zinc (Zn)/cadmium (Cd) hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) was examined to optimize the phytoextraction of metal contaminated soil by two agronomic strategies of intercropping with maize (Zea mays) and plant densities. Soil total Zn and Cd concentrations decreased markedly after long-term phytoextraction. But shoot biomass and Cd and Zn concentrations showed no significant difference with increasing remediation time. In the intercropping experiment the phytoremediation efficiency in the treatment "S. plumbizincicola intercropped with maize" was higher than in S. plumbizincicola monocropping, and Cd concentrations of corn were below the maximum national limit. In the plant density experiment the phytoremediation efficiency increased with increasing plant density and 440,000 plants ha(-1) gave the maximum rate. These results indicated that S. plumbizincicola at an appropriate planting density and intercropped with maize can achieve high remediation efficiency to contaminated soil without affecting the cereal crop productivity. This cropping system combines adequate agricultural production with soil heavy metal phytoextraction.

Alfalfa (Medicago sativa L.)/maize (Zea mays L.) intercropping provides a feasible way to improve yield and economic incomes in farming and pastoral areas of northeast China.

PubMed

Sun, Baoru; Peng, Yi; Yang, Hongyu; Li, Zhijian; Gao, Yingzhi; Wang, Chao; Yan, Yuli; Liu, Yanmei

2014-01-01

Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping modes of maize and alfalfa, a field experiment was conducted in a completely randomized block design with five treatments: maize monoculture in even rows, maize monoculture in alternating wide and narrow rows, alfalfa monoculture, maize intercropped with one row of alfalfa in wide rows and maize intercropped with two rows of alfalfa in wide rows. Results demonstrate that maize monoculture in alternating wide and narrow rows performed best for light transmission, grain yield and output value, compared to in even rows. When intercropped, maize intercropped with one row of alfalfa in wide rows was identified as the optimal strategy and the largely complementary ecological niches of alfalfa and maize were shown to account for the intercropping advantages, optimizing resource utilization and improving yield and economic incomes. These findings suggest that alfalfa/maize intercropping has obvious advantages over monoculture and is applicable to the farming and pastoral areas of northeast China.

Alfalfa (Medicago sativa L.)/Maize (Zea mays L.) Intercropping Provides a Feasible Way to Improve Yield and Economic Incomes in Farming and Pastoral Areas of Northeast China

PubMed Central

Sun, Baoru; Peng, Yi; Yang, Hongyu; Li, Zhijian; Gao, Yingzhi; Wang, Chao; Yan, Yuli; Liu, Yanmei

2014-01-01

Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping modes of maize and alfalfa, a field experiment was conducted in a completely randomized block design with five treatments: maize monoculture in even rows, maize monoculture in alternating wide and narrow rows, alfalfa monoculture, maize intercropped with one row of alfalfa in wide rows and maize intercropped with two rows of alfalfa in wide rows. Results demonstrate that maize monoculture in alternating wide and narrow rows performed best for light transmission, grain yield and output value, compared to in even rows. When intercropped, maize intercropped with one row of alfalfa in wide rows was identified as the optimal strategy and the largely complementary ecological niches of alfalfa and maize were shown to account for the intercropping advantages, optimizing resource utilization and improving yield and economic incomes. These findings suggest that alfalfa/maize intercropping has obvious advantages over monoculture and is applicable to the farming and pastoral areas of northeast China. PMID:25329376

Exposure to Guava Affects Citrus Olfactory Cues and Attractiveness to Diaphorina citri (Hemiptera: Psyllidae).

PubMed

Barman, Jagadish Chandra; Campbell, Stuart A; Zeng, Xinnian

2016-06-01

Intercropping can reduce agricultural pest incidence, and represents an important sustainable alternative to conventional pest control methods. Understanding the ecological mechanisms for intercropping could help optimize its use, particularly in tropical systems which present a large number of intercropping possibilities. Citrus is threatened worldwide by greening disease (huanglongbing, HLB) vectored by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae). Control of HLB and citrus psyllid can be partially achieved through intercropping with guava, Psidium guajava L., but the mechanisms remain unclear. We tested the hypothesis that guava olfactory cues affect psyllid behavior by altering the attractiveness of citrus through plant-plant interactions. In choice and no-choice cage experiments, psyllid settlement was reduced on citrus shoots that had been exposed to guava shoot odors for at least 2 h. In Y-tube olfactometer experiments, psyllids oriented to odors of unexposed, compared with guava-exposed, citrus shoots. These behavioral results indicate that a mechanism for the success of guava intercropping for sustainable, ecological disease management may be the indirect effect of guava on citrus attractiveness. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[Effects of N application on wheat powdery mildew occurrence, nitrogen accumulation and allocation in intercropping system].

PubMed

Zhu, Jin Hui; Dong, Yan; Xiao, Jing Xiu; Zheng, Yi; Tang, Li

2017-12-01

The main objective of this field experiment was to study the effects of wheat and faba bean intercropping on occurrence of wheat powdery mildew, nitrogen content, accumulation and allocation of wheat plant at 4 nitrogen levels of N 0 (0 kg·hm -2 ), N 1 (112.5 kg·hm -2 ), N 2 (225 kg·hm -2 ), N 3 (337.5 kg·hm -2 ), and to explore the relationship between N content, accumulation, allocation and the occurrence of wheat powdery mildew. The results showed that both monocropped and intercropped wheat yields increased with nitrogen application, with the highest yields of monocropped and intercropped wheat being 4146 kg·hm -2 and 4679 kg·hm -2 at N 2 le-vel, respectively. The occurrence and development of wheat powdery mildew become more severe with the increase of N application and area under disease progression curve (AUDPC) were averagely increased by 39.6%-55.6%(calculated with disease incidence, DI) and 92.5%-217.0% (calculated with disease severity index, DSI) with N 1 , N 2 and N 3 treatments. The disease severity index was more affected by nitrogen regulation than by disease incidence. The nitrogen content and accumulation of wheat plant were significantly increased by 8.4%-51.6% and 19.7%-133.7% with nitrogen application, but there was no significant effect on N allocation ratio. Compared with monocropped wheat, yield of intercropped wheat was averagely increased by 12%, whereas, the AUDPC(DI) and AUDPC(DSI) of intercropped wheat were averagely decreased by 11.5% and 30.7%, respectively. The control effect of the disease severity index by intercropping was better than disease incidence. The nitrogen content, accumulation and nitrogen allocation ratio in intercropped wheat leaves were significantly decreased by 6.6%-12.5%, 1.4%-6.9% and 9.0%-15.5% respectively at the peak infection stage of powdery mildew. Overall findings showed that the maximum rate of nitrogen application for wheat should not exceed 225 kg·hm -2 when taking into account both disease control and yield effect.

Effect of chemical and mechanical weed control on cassava yield, soil quality and erosion under cassava cropping system

NASA Astrophysics Data System (ADS)

Islami, Titiek; Wisnubroto, Erwin; Utomo, Wani

2016-04-01

Three years field experiments were conducted to study the effect of chemical and mechanical weed control on soil quality and erosion under cassava cropping system. The experiment were conducted at University Brawijaya field experimental station, Jatikerto, Malang, Indonesia. The experiments were carried out from 2011 - 2014. The treatments consist of three cropping system (cassava mono culture; cassava + maize intercropping and cassava + peanut intercropping), and two weed control method (chemical and mechanical methods). The experimental result showed that the yield of cassava first year and second year did not influenced by weed control method and cropping system. However, the third year yield of cassava was influence by weed control method and cropping system. The cassava yield planted in cassava + maize intercropping system with chemical weed control methods was only 24 t/ha, which lower compared to other treatments, even with that of the same cropping system used mechanical weed control. The highest cassava yield in third year was obtained by cassava + peanuts cropping system with mechanical weed control method. After three years experiment, the soil of cassava monoculture system with chemical weed control method possessed the lowest soil organic matter, and soil aggregate stability. During three years of cropping soil erosion in chemical weed control method, especially on cassava monoculture, was higher compared to mechanical weed control method. The soil loss from chemical control method were 40 t/ha, 44 t/ha and 54 t/ha for the first, second and third year crop. The soil loss from mechanical weed control method for the same years was: 36 t/ha, 36 t/ha and 38 t/ha. Key words: herbicide, intercropping, soil organic matter, aggregate stability.

Root exudates drive interspecific facilitation by enhancing nodulation and N2 fixation

PubMed Central

Li, Bai; Li, Yu-Ying; Wu, Hua-Mao; Zhang, Fang-Fang; Li, Chun-Jie; Li, Xue-Xian; Lambers, Hans; Li, Long

2016-01-01

Plant diversity in experimental systems often enhances ecosystem productivity, but the mechanisms causing this overyielding are only partly understood. Intercropping faba beans (Vicia faba L.) and maize (Zea mays L.) result in overyielding and also, enhanced nodulation by faba beans. By using permeable and impermeable root barriers in a 2-y field experiment, we show that root–root interactions between faba bean and maize significantly increase both nodulation and symbiotic N2 fixation in intercropped faba bean. Furthermore, root exudates from maize promote faba bean nodulation, whereas root exudates from wheat and barley do not. Thus, a decline of soil nitrate concentrations caused by intercropped cereals is not the sole mechanism for maize promoting faba bean nodulation. Intercropped maize also caused a twofold increase in exudation of flavonoids (signaling compounds for rhizobia) in the systems. Roots of faba bean treated with maize root exudates exhibited an immediate 11-fold increase in the expression of chalcone–flavanone isomerase (involved in flavonoid synthesis) gene together with a significantly increased expression of genes mediating nodulation and auxin response. After 35 d, faba beans treated with maize root exudate continued to show up-regulation of key nodulation genes, such as early nodulin 93 (ENOD93), and promoted nitrogen fixation. Our results reveal a mechanism for how intercropped maize promotes nitrogen fixation of faba bean, where maize root exudates promote flavonoid synthesis in faba bean, increase nodulation, and stimulate nitrogen fixation after enhanced gene expression. These results indicate facilitative root–root interactions and provide a mechanism for a positive relationship between species diversity and ecosystem productivity. PMID:27217575

Rational Phosphorus Application Facilitates the Sustainability of the Wheat/Maize/Soybean Relay Strip Intercropping System

PubMed Central

Wang, Ke; Liu, Jing; Lu, Junyu; Xu, Kaiwei

2015-01-01

Wheat (Triticum aestivum L.)/maize (Zea mays L.)/soybean (Glycine max L.) relay strip intercropping (W/M/S) system is commonly used by the smallholders in the Southwest of China. However, little known is how to manage phosphorus (P) to enhance P use efficiency of the W/M/S system and to mitigate P leaching that is a major source of pollution. Field experiments were carried out in 2011, 2012, and 2013 to test the impact of five P application rates on yield and P use efficiency of the W/M/S system. The study measured grain yield, shoot P uptake, apparent P recovery efficiency (PRE) and soil P content. A linear-plateau model was used to determine the critical P rate that maximizes gains in the indexes of system productivity. The results show that increase in P application rates aggrandized shoot P uptake and crops yields at threshold rates of 70 and 71.5 kg P ha-1 respectively. With P application rates increasing, the W/M/S system decreased the PRE from 35.9% to 12.3% averaged over the three years. A rational P application rate, 72 kg P ha-1, or an appropriate soil Olsen-P level, 19.1 mg kg-1, drives the W/M/S system to maximize total grain yield while minimizing P surplus, as a result of the PRE up to 28.0%. We conclude that rational P application is an important approach for relay intercropping to produce high yield while mitigating P pollution and the rational P application-based integrated P fertilizer management is vital for sustainable intensification of agriculture in the Southwest of China. PMID:26540207

Effectiveness of intercropping with soybean as a sustainable farming practice to maintain food production and reduce air pollution in China

NASA Astrophysics Data System (ADS)

Fung, K. M.; Tai, A. P. K.; Yong, T.; Liu, X.

2016-12-01

Agriculture provides the majority of human food sources, but is also an important contributor to an array of environmental problems including air pollution. In China, 96% of ammonia emissions come from agricultural activities, and emitted ammonia contributes more than 20% of fine particulate matter (PM2.5) mass concentrations, with substantial ramification for human health and visibility. Sustainable farming practices that reduce ammonia emissions may therefore have the potential to secure both food production and environmental quality. Intercropping, as such a practice, allows different crops to grow on the same field simultaneously side-by-side. Studies show that it enhances crop yield due to mutualistic crop-crop interactions especially when one of the crops is a legume such as soybean. Below-ground nutrient competition promotes greater nitrogen fixation by soybean, which then induces a greater supply of soil nitrogen not only for soybean itself but also for the other non-nitrogen-fixing crop. To capture this co-benefit, the DNDC biogeochemical model is modified to include the interactive effects between intercropped soybean and maize. We conduct model experiments to compare the performance of a maize-soybean intercropping system and their respective monoculture system in different regions of China. We find that, with intercropping, maize yield can be maintained with only 64% of default fertilizer input, an extra batch of soybean production, and a 52% reduction in ammonia emission, which we calculate to be equivalent to a US$0.94 billion saving per year in terms of pollution-induced health costs. We further estimate the downstream effects on air quality in China using the GEOS-Chem chemical transport model. By reducing ammonia emissions according to the DNDC-simulated results, we find that if maize-soybean intercropping is practiced nationwide, concentrations of ammonium and nitrate in eastern China can be reduced by approximately 4.9% (0.63 μg m-3) and 6.8% (2.1 μg m-3), respectively, and total inorganic PM2.5 decreases by about 3.5% (2.8 μg m-3). This study shows that implementing sustainable farming practices such as maize-soybean intercropping as a national standard in China can possibly relieve air pollution problems while securing a steady food supply with enhanced land-use efficiency.

Potential of Legume–Brassica Intercrops for Forage Production and Green Manure: Encouragements from a Temperate Southeast European Environment

PubMed Central

Jeromela, Ana M.; Mikić, Aleksandar M.; Vujić, Svetlana; Ćupina, Branko; Krstić, Đorđe; Dimitrijević, Aleksandra; Vasiljević, Sanja; Mihailović, Vojislav; Cvejić, Sandra; Miladinović, Dragana

2017-01-01

Legumes and brassicas have much in common: importance in agricultural history, rich biodiversity, numerous forms of use, high adaptability to diverse farming designs, and various non-food applications. Rare available resources demonstrate intercropping legumes and brassicas as beneficial to both, especially for the latter, profiting from better nitrogen nutrition. Our team aimed at designing a scheme of the intercrops of autumn- and spring-sown annual legumes with brassicas for ruminant feeding and green manure, and has carried out a set of field trials in a temperate Southeast European environment and during the past decade, aimed at assessing their potential for yields of forage dry matter and aboveground biomass nitrogen and their economic reliability via land equivalent ratio. This review provides a cross-view of the most important deliverables of our applied research, including eight annual legume crops and six brassica species, demonstrating that nearly all the intercrops were economically reliable, as well as that those involving hairy vetch, Hungarian vetch, Narbonne vetch and pea on one side, and fodder kale and rapeseed on the other, were most productive in both manners. Feeling encouraged that this pioneering study may stimulate similar analyses in other environments and that intercropping annual legume and brassicas may play a large-scale role in diverse cropping systems, our team is heading a detailed examination of various extended research. PMID:28326095

[Effects of Morus alba and Setaria italica intercropping on their plant growth and diurnal variation of photosynthesis].

PubMed

Zhu, Wen-Xu; Zhang, Hui-Hui; Xu, Nan; Wang, Peng; Wang, Shi-Dan; Mu, Shi-Nan; Liang, Ming; Sun, Guang-Yu

2012-07-01

A field investigation was conducted to study the effects of intercropping Morus aIba and Setaria italica on their dry matter production, land use efficiency, and diurnal variation of leaf photosynthesis. Under intercropping, the plant height, basal diameter, root length, and branch number of M. alba increased by 6.0%, 13.7%, 6.8%, and 14.8%, respectively, and the leaf yield of M. alba was increased by 31.3%, as compared with monoculture M. alba. In contrast, the plant height and root length of intercropped S. italica had no significant difference with those of monoculture S. italica. Intercropping enhanced the equivalent ratio and use efficiency of arable land. For both M. alba and S. italica in monoculture or intercropping, their leaf photosynthetic depression all occurred at midday (12 :00), but the leaf photosynthetic depression of monoculture M. alba was heavier than that of intercropped M. alba. Intercropping promoted the leaf stomatal conductance (g(s)) and water use efficiency (WUE) of M. alba at midday, increased the photosynthetic carbon assimilation of M. alba, and inhibited the decline of M. alba leaf actual photochemical efficiency of PS II (phi(PS II)), photosynthetic electron transport rate (ETR), and the maximal photochemical of PS II (F(v)/F(m)) , which might contribute to alleviate the leaf photosynthetic depression of M. alba at midday. It was concluded that M. alba and S. italica intercropping could obviously improve the leaf photosynthetic capacity of M. alba.

[Study of extracting Peucedanum praeruptorum planted area in Ningguo of Anhui province based on multi-source and multi-phase image].

PubMed

Shi, Ting-Ting; Zhang, Xiao-Bo; Zhang, Ke; Guo, Lan-Ping; Huang, Lu-Qi

2017-11-01

The herbs used as the material for traditional Chinese medicine are always planted in the mountainous area where the natural environment is suitable. As the mountain terrain is complex and the distribution of planting plots is scattered, the traditional survey method is difficult to obtain accurate planting area. It is of great significance to provide decision support for the conservation and utilization of traditional Chinese medicine resources by studying the method of extraction of Chinese herbal medicine planting area based on remote sensing and realizing the dynamic monitoring and reserve estimation of Chinese herbal medicines. In this paper, taking the Peucedanum praeruptorum planted area in Ningguo prefecture of Anhui province as an example, the multispectral remote sensing images that include Landsat-8 with a 30 m resolution and China-made GF-1 with a 16 m resolution were used as data source. Since the spectral characteristics of P. praeruptorum in the two periods are different from those of other crops, the changes of the images at two stages in the same year could be used to extract the P. praeruptorum planted area intercropped in cultivated land. Then the texture and spectral characteristics of young pecan trees were used to extract the P. praeruptorum planted area intercropped in woodland. The results showed that the extracted area of planted P. praeruptorum with the original imagery of 30 m spatial resolution and 16 m spatial resolution was 25 635.43,24 585.43 mu, respectively. Copyright© by the Chinese Pharmaceutical Association.

Effects of reduced nitrogen inputs on crop yield and nitrogen use efficiency in a long-term maize-soybean relay strip intercropping system.

PubMed

Chen, Ping; Du, Qing; Liu, Xiaoming; Zhou, Li; Hussain, Sajad; Lei, Lu; Song, Chun; Wang, Xiaochun; Liu, Weiguo; Yang, Feng; Shu, Kai; Liu, Jiang; Du, Junbo; Yang, Wenyu; Yong, Taiwen

2017-01-01

The blind pursuit of high yields via increased fertilizer inputs increases the environmental costs. Relay intercropping has advantages for yield, but a strategy for N management is urgently required to decrease N inputs without yield loss in maize-soybean relay intercropping systems (IMS). Experiments were conducted with three levels of N and three planting patterns, and dry matter accumulation, nitrogen uptake, nitrogen use efficiency (NUE), competition ratio (CR), system productivity index (SPI), land equivalent ratio (LER), and crop root distribution were investigated. Our results showed that the CR of soybean was greater than 1, and that the change in root distribution in space and time resulted in an interspecific facilitation in IMS. The maximum yield of maize under monoculture maize (MM) occurred with conventional nitrogen (CN), whereas under IMS, the maximum yield occurred with reduced nitrogen (RN). The yield of monoculture soybean (MS) and of soybean in IMS both reached a maximum under RN. The LER of IMS varied from 1.85 to 2.36, and the SPI peaked under RN. Additionally, the NUE of IMS increased by 103.7% under RN compared with that under CN. In conclusion, the separation of the root ecological niche contributed to a positive interspecific facilitation, which increased the land productivity. Thus, maize-soybean relay intercropping with reduced N input provides a very useful approach to increase land productivity and avert environmental pollution.

Topography and crop management are key factors for the development of american leaf spot epidemics on coffee in costa rica.

PubMed

Avelino, Jacques; Cabut, Sandrine; Barboza, Bernardo; Barquero, Miguel; Alfaro, Ronny; Esquivel, César; Durand, Jean-François; Cilas, Christian

2007-12-01

ABSTRACT We monitored the development of American leaf spot of coffee, a disease caused by the gemmiferous fungus Mycena citricolor, in 57 plots in Costa Rica for 1 or 2 years in order to gain a clearer understanding of conditions conducive to the disease and improve its control. During the investigation, characteristics of the coffee trees, crop management, and the environment were recorded. For the analyses, we used partial least-squares regression via the spline functions (PLSS), which is a nonlinear extension to partial least-squares regression (PLS). The fungus developed well in areas located between approximately 1,100 and 1,550 m above sea level. Slopes were conducive to its development, but eastern-facing slopes were less affected than the others, probably because they were more exposed to sunlight, especially in the rainy season. The distance between planting rows, the shade percentage, coffee tree height, the type of shade, and the pruning system explained disease intensity due to their effects on coffee tree shading and, possibly, on the humidity conditions in the plot. Forest trees and fruit trees intercropped with coffee provided particularly propitious conditions. Apparently, fertilization was unfavorable for the disease, probably due to dilution phenomena associated with faster coffee tree growth. Finally, series of wet spells interspersed with dry spells, which were frequent in the middle of the rainy season, were critical for the disease, probably because they affected the production and release of gemmae and their viability. These results could be used to draw up a map of epidemic risks taking topographical factors into account. To reduce those risks and improve chemical control, our results suggested that farmers should space planting rows further apart, maintain light shading in the plantation, and prune their coffee trees.

Plant community and white-tailed deer nutritional carrying capacity response to intercropping switchgrass in loblolly pine plantations

NASA Astrophysics Data System (ADS)

Greene, Ethan Jacob

Switchgrass (Panicum virgatum L.) is a cellulosic feedstock for alternative energy production that could grow well between planted pines (Pinus spp.). Southeastern planted pine occupies 15.8 million hectares and thus, switchgrass intercropping could affect biodiversity if broadly implemented. Therefore, I evaluated effects of intercropping switchgrass in loblolly pine (P. taeda L.) plantations on plant community diversity, plant biomass production, and white-tailed deer (Odocoileus virginianus Zimmerman) nutritional carrying capacity. In a randomized complete block design, I assigned three treatments (switchgrass intercropped, switchgrass monoculture, and a "control" of traditional pine management) to 4 replicates of 10-ha experimental units in Kemper County, Mississippi during 2014-2015. I detected 246 different plant species. Switchgrass intercropping reduced plant species richness and diversity but maintained evenness. I observed reduced forb and high-use deer forage biomass but only in intercropped alleys (interbeds). Soil micronutrient interactions affected forage protein of deer plants. White-tailed deer nutritional carrying capacity remained unaffected.

Citrus stand ages regulate the fraction alteration of soil organic carbon under a citrus/Stropharua rugodo-annulata intercropping system in the Three Gorges Reservoir area, China.

PubMed

Zhang, Yang; Ni, Jiupai; Yang, John; Zhang, Tong; Xie, Deti

2017-08-01

Soil carbon fractionation is a valuable indicator in assessing stabilization of soil organic matter and soil quality. However, limited studies have addressed how different vegetation stand ages under intercropping agroforestry systems, could affect organic carbon (OC) accumulation in bulk soil and its physical fractions. A field study thus investigated the impact of citrus plantation age (15-, 25-, and 45-year citrus) on the bulk soil organic carbon (SOC) and SOC fractions and yields of Stropharia rugoso-annulata (SRA) in the Three Gorges Reservoir area, Chongqing, China. Results indicated that the intercropping practice of SRA with citrus significantly increased the SOC by 57.4-61.6% in topsoil (0-10 cm) and by 24.8-39.9% in subsoil (10-30 cm). With a significantly higher enhancement under the 25-year citrus stand than the other two stands, all these citrus stands of three ages also resulted in a significant increase of free particulate OC (fPOC, 60.1-62.4% in topsoil and 34.8-46.7% in subsoil), intra-micro aggregate particulate OC (iPOC, 167.6-206.0% in topsoil and 2.77-61.09% in subsoil), and mineral-associated OC (MOC, 43.6-46.5% in topsoil and 26.0-51.5% in subsoil). However, there were no significant differences in yields of SRA under three citrus stands. Our results demonstrated that citrus stand ages did play an important role in soil carbon sequestration and fractionation under a citrus/SRA intercropping system, which could therefore provide a sustainable agroforestry system to enhance concurrently the SOC accumulation while mitigating farmland CO 2 emission.

How good is the turbid medium-based approach for accounting for light partitioning in contrasted grass--legume intercropping systems?

PubMed

Barillot, Romain; Louarn, Gaëtan; Escobar-Gutiérrez, Abraham J; Huynh, Pierre; Combes, Didier

2011-10-01

Most studies dealing with light partitioning in intercropping systems have used statistical models based on the turbid medium approach, thus assuming homogeneous canopies. However, these models could not be directly validated although spatial heterogeneities could arise in such canopies. The aim of the present study was to assess the ability of the turbid medium approach to accurately estimate light partitioning within grass-legume mixed canopies. Three contrasted mixtures of wheat-pea, tall fescue-alfalfa and tall fescue-clover were sown according to various patterns and densities. Three-dimensional plant mock-ups were derived from magnetic digitizations carried out at different stages of development. The benchmarks for light interception efficiency (LIE) estimates were provided by the combination of a light projective model and plant mock-ups, which also provided the inputs of a turbid medium model (SIRASCA), i.e. leaf area index and inclination. SIRASCA was set to gradually account for vertical heterogeneity of the foliage, i.e. the canopy was described as one, two or ten horizontal layers of leaves. Mixtures exhibited various and heterogeneous profiles of foliar distribution, leaf inclination and component species height. Nevertheless, most of the LIE was satisfactorily predicted by SIRASCA. Biased estimations were, however, observed for (1) grass species and (2) tall fescue-alfalfa mixtures grown at high density. Most of the discrepancies were due to vertical heterogeneities and were corrected by increasing the vertical description of canopies although, in practice, this would require time-consuming measurements. The turbid medium analogy could be successfully used in a wide range of canopies. However, a more detailed description of the canopy is required for mixtures exhibiting vertical stratifications and inter-/intra-species foliage overlapping. Architectural models remain a relevant tool for studying light partitioning in intercropping systems that exhibit strong vertical heterogeneities. Moreover, these models offer the possibility to integrate the effects of microclimate variations on plant growth.

[Effects of mulberry/soybean intercropping on the plant growth and rhizosphere soil microbial number and enzyme activities].

PubMed

Hu, Ju-Wei; Zhu, Wen-Xu; Zhang, Hui-Hui; Xu, Nan; Li, Xin; Yue, Bing-Bing; Sun, Guang-yu

2013-05-01

A root separation experiment was conducted to investigate the plant growth and rhizosphere soil microbes and enzyme activities in a mulberry/soybean intercropping system. As compared with those in plastic barrier and nylon mesh barrier treatments, the plant height, leaf number, root length, root nodule number, and root/shoot ratio of mulberry and soybean in non-barrier treatment were significantly higher, and the soybean's effective nodule number was larger. The available phosphorous content in the rhizosphere soils of mulberry and soybean in no barrier and nylon mesh barrier treatments was increased by 10.3% and 11.1%, and 5.1% and 4.6%, respectively, as compared with that in plastic barrier treatment. The microbial number, microbial diversity, and enzyme activities in the rhizosphere soils of mulberry and soybean were higher in the treatments of no barrier and nylon mesh barrier than in the treatment of plastic barrier. All the results indicated that there was an obvious interspecific synergistic effect between mulberry and soybean in the mulberry/soybean intercropping system.

Switchgrass growth and pine-switchgrass interactions in established intercropping systems

DOE PAGES

Tian, Shiying; Cacho, Julian F.; Youssef, Mohamed A.; ...

2016-06-22

Intercropping switchgrass ( Panicum virgatum L.) with loblolly pine ( Pinus taeda L.) has been proposed for producing bioenergy feedstock in the southeastern United States. This study investigated switchgrass growth and pine–switchgrass interactions at two established experimental fields (7-year-old Lenoir site and 5-year-old Carteret site) located on the coastal plain of eastern United States. Position effects (edge and center of switchgrass alley in intercropping plots) and treatment effects (intercropping vs. grass-only) on above ground switchgrass growth were evaluated. Interspecific interactions with respect to capturing resources (light, soil water, and nitrogen) were investigated by measuring photosynthetically active radiation (PAR) above grassmore » canopy, soil moisture, and soil mineral nitrogen contents. Switchgrass growth was significantly (P = 0.001) affected by treatments in Lenoir and by position (P < 0.0001) in both study sites. Relative to the center, PAR above grass canopy at edge in both sites was about 48% less during the growing season. Soil water content during the growing season at the edge of grass alley was significantly (P = 0.0001) lower by 23% than at the center in Lenoir, while no significant (P = 0.42) difference was observed in Carteret, in spite of more grass growth at center at both sites. Soil mineral nitrogen content at the center of intercropping plots in Lenoir (no fertilization during 2015) was significantly (P < 0.07) lower than at the edge during the peak of growing season (June, July, and August), but not during early and late parts of growing season (May, September, and November). Position effects on soil water and mineral nitrogen were less evident under conditions with higher external inputs (rainfall and fertilization) and lower plant uptake during nongrowing seasons. Here, results from this study contributed to a better understanding of above- and belowground pine–switchgrass interactions which is necessary to properly manage this new cultivation system for bioenergy production in the southeastern United States.« less

Intercropping of oat and field pea in Alaska: an alternative approach to quality forage production and weed control

USDA-ARS?s Scientific Manuscript database

Intercropping of legumes with non-legumes is an ancient crop production method used to improve quality and dry matter (DM) yields of forage and grain, and to control weeds. However, there is little information regarding intercropping at high latitudes. The objectives of this field study were to eval...

[Effects of phosphorus application rates and depths on P utilization and loss risk in a maize-soybean intercropping system].

PubMed

Zhao, Wei; Song, Chun; Zhou, Pan; Wang, Jia Yu; Xui, Feng; Ye, Fang; Wang, Xiao Chun; Yang, Wen Yu

2018-04-01

In order to explore the advantage of intercropping on phosphorus (P) efficient utilization and the reduction of soil P loss, a field experiment in a maize-soybean intercropping system, which included three P application (P 2 O 5 ) rates (CP: 168 kg·hm -2 ; RP 1 : 135 kg·hm -2 ; RP 2 : 101 kg·hm -2 ) and three P application depths (D 1 : applied in 5 cm depth; D 2 : applied in 15 cm depth; D 3 : 1/2 of P fertilizer applied in 5 cm depth and another 1/2 in 15 cm depth) was carried out to analyze the effects of P application rates and depth on crop aboveground biomass, grain yield, crop P uptake, soil total and available P contents, and soil P adsorption-desorption characteristics. Compared with control treatment, the aboveground biomass, grain yield, crop P uptake, soil total P, and available P content were increased significantly by P application, regardless of P rate and application depth. Under the same application depth, RP 1 had similar grain yield but higher crop P uptake compared with CP, and thus higher P apparent utilization efficiency. Under the same P application rate, the application depth of D 2 had the highest crop aboveground biomass, grain yield, P uptake, soil total P, and available P. According to the characteristic of soil P adsorption-desorption, the treatment with the rate of RP 1 and the depth of D 2 had the strongest soil P retention capacity, which had advantage in alleviating P loss. These results suggested that reducing application rate but increasing application depth of P fertilizer could improve P use efficiency and reduce soil P loss without sacrifice in crop production in maize-soybean relay intercropping system.

Sustainable, alternative farming practices as a means to simultaneously secure food production and reduce air pollution in East Asia

NASA Astrophysics Data System (ADS)

Tai, A. P. K.; Fung, K. M.; Yong, T.; Liu, X.

2015-12-01

Proper agricultural land management is essential for securing food supply and minimizing damage to the environment. Among available farming practices, relay strip intercropping and fertilizer application are commonly used, but to study their wider environmental implications and possible feedbacks we require an Earth system modeling framework. In this study, the effectiveness of a maize-soybean relay strip intercropping system and fertilizer reduction is investigated using a multi-model method. The DNDC (DeNitrification-DeComposition) model is used to simulate agricultural activities and their impacts on the environment through nitrogen emissions and changes in soil chemical composition. Crop yield, soil nutrient content and nitrogen emissions to the atmosphere in major agricultural regions of China are predicted under various cultivation scenarios. The GEOS-Chem global chemical transport model is then used to estimate the effects on downwind particle and ozone air pollution. We show that relay strip intercropping and optimal fertilization not only improve crop productivity, but also retain soil nutrients, reduce ammonia emission and mitigate downwind air pollution. By cutting 25% fertilization inputs but cultivating maize and soybean together in a relay strip intercropping system used with field studies, total crop production was improved slightly by 4.4% compared to monoculture with conventional amount of fertilizers. NH3 volatilization decreases by 29%, equivalent to saving the pollution-induced health damage costs by about US$2.5 billion per year. The possible feedback effects from atmospheric nitrogen deposition onto the croplands are also investigated. We show that careful management and better quantitative understanding of alternative farming practices hold huge potential in simultaneously addressing different global change issues including the food crisis, air pollution and climate change, and calls for greater collaboration between scientists, farmers and policy makers concerning these issues.

Agro-Forestry system in West Africa: integrating a green solution to cope with soil depletion towards agricultural sustainability

NASA Astrophysics Data System (ADS)

Monteiro, Filipa; Vidigal, Patricia; Romeiras, Maria Manuel; Ribeiro, Ana; Abreu, Maria Manuela; Viegas, Wanda; Catarino, Luís

2017-04-01

During the last decades, agriculture in West Africa has been marked by dramatic shifts with the coverage of single crops, increasing pressure over the available arable land. Yet, West African countries are still striving to achieve sustainable production at an increased scale for global market needs. Market-driven rapid intensification is often a major cause for cropland area expansion at the expense of deforestation and soil degradation, especially to export commodities in times of high prices. Cashew (Anacardium occidentale L.) is nowadays an important export-oriented crop, being produced under intensive cultivation regimes in several tropical regions. Particularly, among the main cashew production areas, West Africa is the most recent and dynamic in the world, accounting for 45% of the world cashew nuts production in 2015. Considering its global market values, several developing countries rely on cashew nuts as national economy revenues, namely in Guinea-Bissau. Considering the intensive regime of cashew production in Guinea-Bissau, and as widely recognized, intensive agriculture linked with extensification can negatively impact ecosystems, affecting natural resources availability, soil erosion and arability compromised by excessive salinity. Ultimately this will result in the disruption of carbon - nitrogen cycle, important to the agricultural ecosystem sustainability. As such, tree intercropped with legumes as cover crops, offers a sustainable management of the land area, thus creating substantial benefits both economically and environmentally, as it enhances diversification of products outputs and proving to be more sustainable than forestry and/or agricultural monocultures. Soil fertility improvement is a key entry point for achieving food security, and also increment agriculture commodities of the agro-system. Without using inorganic fertilizers, the green solution for improving soil management is to incorporate adapted multi-purpose legumes as cover crops, reducing soil erosion as well as insect pests and associated diseases, while improves the yield of the main crop. The integration of legume in agroforestry systems offers an alternative and resilient strategy to increase N availability without increasing mineral N additions. As such, we present a case study of a forest-based system under intensive agriculture regime and propose an alternative sustainable system - the agroforestry system - by intercropping legumes, thus ensuring the sustainability of a cash crop sector both in terms of food security and soil resources. Results obtained from this case-study will therefore be important to demonstrate the global importance of agroforestry systems as key strategy for land use planning, sustainability of the agricultural systems as well as the preserving the environment of smallholder farms in the sub-Saharan Africa.

Designing Agricultural Development Projects for the Small Scale Farmers: Some Lessons from the World Bank Assistance Small Holder Oil Palm Development Scheme in Nigeria

NASA Astrophysics Data System (ADS)

Orewa, S. I.

The study was carried out to investigate farmers reasons for intercropping their oil palm farms with food and other cash crops rather than the sole oil palm planting arrangement specified for participation in the World Bank Assistance Smallholder Oil Palm development project financed during the 1975-83 period. The study was conducted at the Ekuku-Agbor Tree Crop Unit Zone (to the East) and Mosogar Tree Crop Unit Zone (to the Southwest) of the old Bendel State of Nigeria. A total of 35 oil palm farmers were randomly selected from each zone for the study. The study tried to identify the size of oil palm cultivated, types of food and cash crops planted and the proportion consumed and sold and the sufficiency of labour for various farm activities. The study showed that the average oil palm farm size at Ekuku-Agbor zone was smaller (about 1.57 ha) and more fragmented while for Mosogar zone it was 2.28 ha. However a greater percentage (over 65%) of the farms at both locations were within 0.01-2.00 ha farm size range which could be said to be relatively small. The study revealed that among other factors the farmers desire to ensure adequate family food needs which equates to food security and some cash to meet regular family financial needs necessitated their intercropping of the oil palm farms. Others include the need to maximize the returns from the use of labour which they considered a major limiting factor in farm maintenance and to take advantage of the relative high unit price of cassava and its products that prevailed then by cultivating on any available land space including the palm plantations and thereby increasing their farm income.

The effect of monoculture peanut and cassava/peanut intercropping on physical and chemical properties in peanut rhizosphere soil under the biochar application and straw mulching

NASA Astrophysics Data System (ADS)

Chen, X.; Tian, Y.; Guo, X. F.; Chen, G. K.; He, H. Z.; Li, H. S.

2017-03-01

Cassava/peanut intercropping is a popular cultivation method in the south China, with the advantage of apparent yield increase. In order to analyze the effect of cassava/peanut intercropping on physical and chemical properties in peanut rhizosphere soil, the physical and chemical properties were investigated under the biochar application and straw mulching. The result showed that the Ph, organic materials content, available phosphorus content, available potassium content in peanut rhizosphere under the biochar application increased by 7.06%, 94.52%, 17.53%, 25.08% (monoculture peanut) and 8.47%, 89.94%, 17.93%, 22.87% (cassava/peanut intercropping) compared with Ck in the same planting patterns. In addition, the available nitrogen content, organic materials content, available phosphorus content, and available potassium content in peanut rhizosphere under the straw mulching increased by 89.80%, 60.92%, 5.95%, 9.98% (monoculture peanut) and 67.09%, 52.34%, 6.96%, 11.94% (cassava/peanut intercropping) compared with Ck in the same planting patterns. In the same treatment conditions, bulk density in peanut rhizosphere soil decreased and porosity and saturated permeability coefficient increased slightly. But there was no significant difference between the two. At the same time, cassava/peanut intercropping could increase soil nutrients. Therefore, it is beneficial to apply biochar and straw mulching, and the suitable intercropping row spacing is more beneficial to increase soil nutrient contents.

Phosphorous fractions in soils of rubber-based agroforestry systems: Influence of season, management and stand age.

PubMed

Liu, Chenggang; Jin, Yanqiang; Liu, Changan; Tang, Jianwei; Wang, Qingwei; Xu, Mingxi

2018-03-01

Rubber-based agroforestry system is a vital management practice and its productivity is often controlled by soil phosphorus (P) nutrient, but little information is available on P fractions dynamics in such system. The aim of this study was to examine the seasonal, management and stand age effects on P fractions, acid phosphatase activity, microbial biomass P, other physical-chemical properties and litter and roots in four systems: 10-year-old rubber mono- (YM) and intercropping (YI) with N-fixing species (NFS), 22-year-old mono- (MM) and intercropping (MI) in Xishuangbanna, Southwestern China. Most P fractions varied seasonally at different depths, with highest values in the fog-cool season (i.e. labile P at 5-60cm, non-labile P and total P at 30-60cm). By contrast, moderately labile P varied little over time, except in MI that had lower values in the rainy season. Compared with their monoculture counterparts, YI doubled resin-P i concentration but decreased NaHCO 3 -extractable P, HCl-P i and residual-P o at the 0-30cm depth, whereas MI had hardly any changes in P species at the 60-cm depth. Surprisingly, residual-P o was enriched down to the deepest soil (30-60cm) in both YI and MI in the fog-cool season. All P fractions, except NaOH 0.1 -P i , were greatly reduced with increasing stand age. In addition to plants uptake, these changes can be explained by seasonality in soil environments (e.g. moisture, temperature, pH and microbial activity) and decomposition of litter and roots. Moreover, YI decreased labile P o stock, but MI increased moderately labile P i at the 60-cm depth across seasons. The results imply that a large amount of residual-P o exists in acidic Oxisol from China and that they can be reasonably exploited to reduce the application of P fertilizers, highlighting the importance of P o pool. Taken together, intercropping mature rubber plantation with NFS appears to be an effective way to enhance productivity while maintaining adequate soil P concentration over the long run. Copyright © 2017 Elsevier B.V. All rights reserved.

[Transpiration of Choerospondias axillaris in agro-forestrial system and its affecting factors].

PubMed

Zhao, Ying; Zhang, Bin; Zhao, Huachun; Wang, Mingzhu

2005-11-01

Measurement of transpiration is essential to assess plant water use efficiency. Applying Grainer method, this paper measured the sap flow of Choerospondias axillaries in an agro-forestrial system, aimed to evaluate the effects of intercropping and pruning on the diurnal variation of transpiration, and to relate the transpiration rate with climatic factors. The results showed that the diurnal variation of Choerospondias arillaries transpiration rate appeared in parabola, low in the morning and evening, and high at noon. The transpiration rate was closely related to leaf stomatal conductivity and soil water potential, especially the water potential in 100 cm soil depth (R = 0.737). The transpiration rate of Choerospondias axillaries was increased by about 40% approximately 160% in agro-forestrial system through the changes in regional environment and in the deep soil water use by tree. Correlation analysis and multi-factor successive regression analysis indicated that the transpiration was controlled by ray radiation intensity, air temperature and ground temperature, followed by the difference between saturated and actual vapor pressure and the wind speed. A statistical model for calculating the sap flow rate by micrometeorological factors was also provided.

Effects of Intercropping with Potato Onion on the Growth of Tomato and Rhizosphere Alkaline Phosphatase Genes Diversity

PubMed Central

Wu, Xia; Wu, Fengzhi; Zhou, Xingang; Fu, Xuepeng; Tao, Yue; Xu, Weihui; Pan, Kai; Liu, Shouwei

2016-01-01

Background and Aims: In China, excessive fertilization has resulted in phosphorus (P) accumulation in most greenhouse soils. Intercropping can improve the efficiency of nutrient utilization in crop production. In this study, pot experiments were performed to investigate the effects of intercropping with potato onion (Allium cepa L. var. aggregatum G. Don) on tomato (Solanum lycopersicum L.) seedlings growth and P uptake, the diversity of rhizosphere phosphobacteria and alkaline phosphatase (ALP) genes in phosphorus-rich soil. Methods: The experiment included three treatments, namely tomato monoculture (TM), potato onion monoculture (OM), and tomato/potato onion intercropping (TI-tomato intercropping and OI-potato onion intercropping). The growth and P uptake of tomato and potato onion seedlings were evaluated. The dilution plating method was used to determine the population of phosphate-solubilizing bacteria (PSB) and phosphate-mineralizing bacteria (PMB). The genomic DNAs of PSB and PMB in the rhizosphere of tomato and potato onions were extracted and purified, and then, with the primer set of 338f /518r, the PCR amplification of partial bacterial 16S rDNA sequence was performed and sequenced to determine the diversities of PSB and PMB. After extracting the total genomic DNAs from the rhizosphere, the copy numbers and diversities of ALP genes were investigated using real-time PCR and PCR-DGGE, respectively. Results: Intercropping with potato onion promoted the growth and P uptake of tomato seedlings, but inhibited those of potato onion. After 37 days of transplanting, compared to the rhizosphere of TM, the soil pH increased, while the electrolytic conductivity and Olsen P content decreased (p < 0.05) in the rhizosphere of TI. The populations and diversities of PSB, PMB, and ALP genes increased significantly in the rhizosphere of TI, compared to the rhizosphere of TM. Conclusion: The results indicated that intercropping with potato onion promoted the growth and P uptake of tomato in phosphorus-rich soil and affected the community structure and function of phosphobacteria in tomato rhizosphere. Intercropping with potato onion also improved soil quality by lowering levels of soil acidification and salinization. PMID:27379133

The intercropping partner affects arbuscular mycorrhizal fungi and Fusarium oxysporum f. sp. lycopersici interactions in tomato.

PubMed

Hage-Ahmed, Karin; Krammer, Johannes; Steinkellner, Siegrid

2013-10-01

Arbuscular mycorrhizal fungi (AMF) and their bioprotective aspects are of great interest in the context of sustainable agriculture. Combining the benefits of AMF with the utilisation of plant species diversity shows great promise for the management of plant diseases in environmentally compatible agriculture. In the present study, AMF were tested against Fusarium oxysporum f. sp. lycopersici with tomato intercropped with either leek, cucumber, basil, fennel or tomato itself. Arbuscular mycorrhizal (AM) root colonisation of tomato was clearly affected by its intercropping partners. Tomato intercropped with leek showed even a 20 % higher AM colonisation rate than tomato intercropped with tomato. Positive effects of AMF expressed as an increase of tomato biomass compared to the untreated control treatment could be observed in root as well as in shoot weights. A compensation of negative effects of F. oxysporum f. sp. lycopersici on tomato biomass by AMF was observed in the tomato/leek combination. The intercropping partners leek, cucumber, basil and tomato had no effect on F. oxysporum f. sp. lycopersici disease incidence or disease severity indicating no allelopathic suppression; however, tomato co-cultivated with tomato clearly showed a negative effect on one plant/pot with regard to biomass and disease severity of F. oxysporum f. sp. lycopersici. Nonetheless, bioprotective effects of AMF resulting in the decrease of F. oxysporum f. sp. lycopersici disease severity were evident in treatments with AMF and F. oxysporum f. sp. lycopersici co-inoculation. However, these bioprotective effects depended on the intercropping partner since these effects were only observed in the tomato/leek and tomato/basil combination and for the better developed plant of tomato/tomato. In conclusion, the effects of the intercropping partner on AMF colonisation of tomato are of great interest for crop plant communities and for the influences on each other. The outcome of the bioprotective effects of AMF resulting in the decrease on F. oxysporum f. sp. lycopersici disease severity and/or compensation of plant biomass does not depend on the degree of AM colonisation but more on the intercropping partner.

Effects of Intercropping with Potato Onion on the Growth of Tomato and Rhizosphere Alkaline Phosphatase Genes Diversity.

PubMed

Wu, Xia; Wu, Fengzhi; Zhou, Xingang; Fu, Xuepeng; Tao, Yue; Xu, Weihui; Pan, Kai; Liu, Shouwei

2016-01-01

In China, excessive fertilization has resulted in phosphorus (P) accumulation in most greenhouse soils. Intercropping can improve the efficiency of nutrient utilization in crop production. In this study, pot experiments were performed to investigate the effects of intercropping with potato onion (Allium cepa L. var. aggregatum G. Don) on tomato (Solanum lycopersicum L.) seedlings growth and P uptake, the diversity of rhizosphere phosphobacteria and alkaline phosphatase (ALP) genes in phosphorus-rich soil. The experiment included three treatments, namely tomato monoculture (TM), potato onion monoculture (OM), and tomato/potato onion intercropping (TI-tomato intercropping and OI-potato onion intercropping). The growth and P uptake of tomato and potato onion seedlings were evaluated. The dilution plating method was used to determine the population of phosphate-solubilizing bacteria (PSB) and phosphate-mineralizing bacteria (PMB). The genomic DNAs of PSB and PMB in the rhizosphere of tomato and potato onions were extracted and purified, and then, with the primer set of 338f /518r, the PCR amplification of partial bacterial 16S rDNA sequence was performed and sequenced to determine the diversities of PSB and PMB. After extracting the total genomic DNAs from the rhizosphere, the copy numbers and diversities of ALP genes were investigated using real-time PCR and PCR-DGGE, respectively. Intercropping with potato onion promoted the growth and P uptake of tomato seedlings, but inhibited those of potato onion. After 37 days of transplanting, compared to the rhizosphere of TM, the soil pH increased, while the electrolytic conductivity and Olsen P content decreased (p < 0.05) in the rhizosphere of TI. The populations and diversities of PSB, PMB, and ALP genes increased significantly in the rhizosphere of TI, compared to the rhizosphere of TM. The results indicated that intercropping with potato onion promoted the growth and P uptake of tomato in phosphorus-rich soil and affected the community structure and function of phosphobacteria in tomato rhizosphere. Intercropping with potato onion also improved soil quality by lowering levels of soil acidification and salinization.

Population dynamics of Aphis gossypii Glover and in sole and intercropping systems of cotton and cowpea.

PubMed

Fernandes, Francisco S; Godoy, Wesley A C; Ramalho, Francisco S; Garcia, Adriano G; Santos, Bárbara D B; Malaquias, José B

2018-01-01

Population dynamics of aphids have been studied in sole and intercropping systems. These studies have required the use of more precise analytical tools in order to better understand patterns in quantitative data. Mathematical models are among the most important tools to explain the dynamics of insect populations. This study investigated the population dynamics of aphids Aphis gossypii and Aphis craccivora over time, using mathematical models composed of a set of differential equations as a helpful analytical tool to understand the population dynamics of aphids in arrangements of cotton and cowpea. The treatments were sole cotton, sole cowpea, and three arrangements of cotton intercropped with cowpea (t1, t2 and t3). The plants were infested with two aphid species and were evaluated at 7, 14, 28, 35, 42, and 49 days after the infestations. Mathematical models were used to fit the population dynamics of two aphid species. There were good fits for aphid dynamics by mathematical model over time. The highest population peak of both species A. gossypii and A. craccivora was found in the sole crops, and the lowest population peak was found in crop system t2. These results are important for integrated management programs of aphids in cotton and cowpea.

[Effects of intercropping Sedum plumbizincicola and Apium graceolens on the soil chemical and microbiological properties under the contamination of zinc and cadmium from sewage sludge application].

PubMed

Nai, Feng-Jiao; Wu, Long-Hua; Liu, Hong-Yan; Ren, Jing; Liu, Wu-Xing; Luo, Yong-Ming

2013-05-01

Taking the vegetable soil with zinc- and cadmium contamination from a long-term sewage sludge application as the object, a pot experiment was conducted to study the remediation effect of Sedum plumbizincicola and Apium graceolens under continuous monoculture and intercropping. With the remediation time increased, both S. plumbizincicola and A. graceolens under monoculture grew poorly, but S. plumbizincicola under intercropping grew well. Under intercropping, the soil organic matter, total N, extractable N, and total P contents decreased significantly while the soil extractable K content had a significant increase, the counts of soil bacteria and fungi increased by 7.9 and 18.4 times and 3.7 and 4.3 times, respectively, but the soil urease and catalase activities remained unchanged, as compared with those under A. graceolens and S. plumbizincicola monoculture. The BIOLOG ECO micro-plates also showed that the carbon sources utilization level and the functional diversity index of soil microbial communities were higher under intercropping than under monoculture, and the concentrations of soil zinc and cadmium under intercropping decreased by 5.8% and 50.0%, respectively, with the decrements being significantly higher than those under monoculture. It was suggested that soil microbial effect could be one of the important factors affecting plant growth.

A field study on heavy metals phytoattenuation potential of monocropping and intercropping of maize and/or legumes in weakly alkaline soils.

PubMed

Zhu, Saiyong; Ma, Xinwang; Guo, Rui; Ai, Shiwei; Liu, Bailin; Zhang, Wenya; Zhang, Yingmei

2016-10-02

The study focused on the phytoattenuation effects of monocropping and intercropping of maize (Zea mays) and/or legumes on Cu, Zn, Pb, and Cd in weakly alkaline soils. Nine growth stages of monocropping maize were chosen to study the dynamic process of extraction of heavy metals. The total content of heavy metals extracted by the aerial part of monocropped maize increased in a sigmoidal pattern over the effective accumulative temperature. The biggest biomass, highest extraction content, and lowest heavy metals bioaccumulation level occurred at physiological maturity. Among the different planting patterns, including monocropping and intercropping of maize and/or soybean (Glycine max), pea (Pisum sativum), and alfalfa (Medicago sativa), the extraction efficiency of Cu, Zn, Pb, and Cd varied greatly. Only intercropping of maize and soybean yielded relatively higher extraction efficiency for the four metals with no significant difference in the total biomass. Moreover, the heavy metals concentrations in dry biomass from all the planting patterns in the present study were within China's national legal thresholds for fodder use. Therefore, slightly polluted alkaline soils can be safely used through monocropping and intercropping of maize and/or legumes for a range of purposes. In particular, this study indicated that intercropping improves soil ecosystems polluted by heavy metals compared with monocropping.

Achieving food security for one million sub-Saharan African poor through push-pull innovation by 2020.

PubMed

Khan, Zeyaur R; Midega, Charles A O; Pittchar, Jimmy O; Murage, Alice W; Birkett, Michael A; Bruce, Toby J A; Pickett, John A

2014-04-05

Food insecurity is a chronic problem in Africa and is likely to worsen with climate change and population growth. It is largely due to poor yields of the cereal crops caused by factors including stemborer pests, striga weeds and degraded soils. A platform technology, 'push-pull', based on locally available companion plants, effectively addresses these constraints resulting in substantial grain yield increases. It involves intercropping cereal crops with a forage legume, desmodium, and planting Napier grass as a border crop. Desmodium repels stemborer moths (push), and attracts their natural enemies, while Napier grass attracts them (pull). Desmodium is very effective in suppressing striga weed while improving soil fertility through nitrogen fixation and improved organic matter content. Both companion plants provide high-value animal fodder, facilitating milk production and diversifying farmers' income sources. To extend these benefits to drier areas and ensure long-term sustainability of the technology in view of climate change, drought-tolerant trap and intercrop plants are being identified. Studies show that the locally commercial brachiaria cv mulato (trap crop) and greenleaf desmodium (intercrop) can tolerate long droughts. New on-farm field trials show that using these two companion crops in adapted push-pull technology provides effective control of stemborers and striga weeds, resulting in significant grain yield increases. Effective multi-level partnerships have been established with national agricultural research and extension systems, non-governmental organizations and other stakeholders to enhance dissemination of the technology with a goal of reaching one million farm households in the region by 2020. These will be supported by an efficient desmodium seed production and distribution system in eastern Africa, relevant policies and stakeholder training and capacity development.

Growth and physiological changes in continuously cropped eggplant (Solanum melongena L.) upon relay intercropping with garlic (Allium sativum L.)

PubMed Central

Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen

2015-01-01

Relay intercropping represents an alternative for sustainable production of vegetables, but the changes of internally antioxidant defense combined with the growth and yield are not clear. Field experiment was carried out to investigate the malondialdehyde (MDA) content and activity levels of superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) in eggplant (Solanum melongena L.) and plant height, stem diameter, maximal leaf area, and yield of eggplant grown under successive cropping in the year 2011 and 2012 to see if relay intercropping with garlic (Allium sativum L.) could benefit to eggplant growth and yield. Three experimental treatments with three repeats in each were carried out (completely randomized block design): eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG), and eggplant relay intercropping with green garlic (GG). In both years, the MDA content was significantly lower and SOD and POD activities were generally lower in NG and GG compared with CK in most sampling dates. PPO activity trends were generally opposite to those of POD. The general trend of PAL activity was similar to MDA. The plant height and stem of eggplant was lower, but the maximal leaf area was larger in NG and GG in 2011; in 2012 the plant growth was stronger in relay intercropping treatments. For eggplant yield in 2011, NG was 2.85% higher than CK; after the time for the green garlic pulled out was moved forward in 2012, the yield was increased by 6.26 and 7.80%, respectively, in NG and GG. The lower MDA content and enzyme activities in relay intercropping treatments showed that the eggplant suffered less damage from environment and continuous cropping obstacles, which promoted healthier plant. Thus from both the growth and physiological perspective, it was concluded that eggplant/garlic relay intercropping is a beneficial cultivation practice maintaining stronger plant growth and higher yield. PMID:25964788

Growth and physiological changes in continuously cropped eggplant (Solanum melongena L.) upon relay intercropping with garlic (Allium sativum L.).

PubMed

Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen

2015-01-01

Relay intercropping represents an alternative for sustainable production of vegetables, but the changes of internally antioxidant defense combined with the growth and yield are not clear. Field experiment was carried out to investigate the malondialdehyde (MDA) content and activity levels of superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) in eggplant (Solanum melongena L.) and plant height, stem diameter, maximal leaf area, and yield of eggplant grown under successive cropping in the year 2011 and 2012 to see if relay intercropping with garlic (Allium sativum L.) could benefit to eggplant growth and yield. Three experimental treatments with three repeats in each were carried out (completely randomized block design): eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG), and eggplant relay intercropping with green garlic (GG). In both years, the MDA content was significantly lower and SOD and POD activities were generally lower in NG and GG compared with CK in most sampling dates. PPO activity trends were generally opposite to those of POD. The general trend of PAL activity was similar to MDA. The plant height and stem of eggplant was lower, but the maximal leaf area was larger in NG and GG in 2011; in 2012 the plant growth was stronger in relay intercropping treatments. For eggplant yield in 2011, NG was 2.85% higher than CK; after the time for the green garlic pulled out was moved forward in 2012, the yield was increased by 6.26 and 7.80%, respectively, in NG and GG. The lower MDA content and enzyme activities in relay intercropping treatments showed that the eggplant suffered less damage from environment and continuous cropping obstacles, which promoted healthier plant. Thus from both the growth and physiological perspective, it was concluded that eggplant/garlic relay intercropping is a beneficial cultivation practice maintaining stronger plant growth and higher yield.

[Effects of tobacco garlic crop rotation and intercropping on tobacco yield and rhizosphere soil phosphorus fractions].

PubMed

Tang, Biao; Zhang, Xi-zhou; Yang, Xian-bin

2015-07-01

A field plot experiment was conducted to investigate the tobacco yield and different forms of soil phosphorus under tobacco garlic crop rotation and intercropping patterns. The results showed that compared with tobacco monoculture, the tobacco yield and proportion of middle/high class of tobacco leaves to total leaves were significantly increased in tobacco garlic crop rotation and intercropping, and the rhizosphere soil available phosphorus contents were 1.3 and 1.7 times as high as that of tobacco monoculture at mature stage of lower leaf. For the inorganic phosphorus in rhizosphere and non-rhizosphere soil in different treatments, the contents of O-P and Fe-P were the highest, followed by Ca2-P and Al-P, and Ca8-P and Ca10-P were the lowest. Compared with tobacco monoculture and tobacco garlic crop intercropping, the Ca2-P concentration in rhizosphere soil under tobacco garlic crop rotation at mature stage of upper leaf, the Ca8-P concentration at mature stage of lower leaf, and the Ca10-P concentration at mature stage of middle leaf were lowest. The Al-P concentrations under tobacco garlic crop rotation and intercropping were 1.6 and 1.9 times, and 1.2 and 1.9 times as much as that under tobacco monoculture in rhizosphere soil at mature stages of lower leaf and middle leaf, respectively. The O-P concentrations in rhizosphere soil under tobacco garlic crop rotation and intercropping were significantly lower than that under tobacco monoculture. Compared with tobacco garlic crop intercropping, the tobacco garlic crop rotation could better improve tobacco yield and the proportion of high and middle class leaf by activating O-P, Ca10-P and resistant organic phosphorus in soil.

Interplanting Annual Ryegrass, Wheat, Oat, and Corn to Mitigate Iron Deficiency in Dry Beans

PubMed Central

Omondi, Emmanuel Chiwo; Kniss, Andrew R.

2014-01-01

This study evaluated whether grass intercropping can be used to alleviate Fe deficiency chlorosis in dry beans (Phaseolus vulgaris L.) grown in high pH, calcareous soils with low organic matter. Field studies were conducted at the University of Wyoming Sustainable Agriculture Research and Extension Center in 2009 and 2010. Black- and navy beans were grown alone or intercropped with annual ryegrass (Lolium multiflorum Lam.), oat (Avena sativa L.), corn (Zea mays L.), or spring wheat (Triticum aestivum L.) in a two-factor factorial strip-plot randomized complete block design. All four grass species increased chlorophyll intensity in dry beans. However, grass species did not increase iron (Fe) concentration in dry bean tissues suggesting inefficient utilization of Fe present in the dry bean tissues. In 2009, nitrate-nitrogen (NO3-N) and manganese (Mn) concentration in bean tissue were greater in bean monoculture than in grass intercropped beans. Bean monoculture also had greater soil NO3-N concentrations than grass intercropped treatments. In 2009, grass intercrops reduced dry bean yield >25% compared to bean monoculture. Annual ryegrass was the least competitive of the four annual grass species. This suggests that competition from grasses for nutrients, water, or light may have outweighed benefits accruing from grass intercropping. Additional studies are required to determine the appropriate grass and dry bean densities, as well as the optimum time of grass removal. PMID:25536084

Interplanting annual ryegrass, wheat, oat, and corn to mitigate iron deficiency in dry beans.

PubMed

Omondi, Emmanuel Chiwo; Kniss, Andrew R

2014-01-01

This study evaluated whether grass intercropping can be used to alleviate Fe deficiency chlorosis in dry beans (Phaseolus vulgaris L.) grown in high pH, calcareous soils with low organic matter. Field studies were conducted at the University of Wyoming Sustainable Agriculture Research and Extension Center in 2009 and 2010. Black- and navy beans were grown alone or intercropped with annual ryegrass (Lolium multiflorum Lam.), oat (Avena sativa L.), corn (Zea mays L.), or spring wheat (Triticum aestivum L.) in a two-factor factorial strip-plot randomized complete block design. All four grass species increased chlorophyll intensity in dry beans. However, grass species did not increase iron (Fe) concentration in dry bean tissues suggesting inefficient utilization of Fe present in the dry bean tissues. In 2009, nitrate-nitrogen (NO3-N) and manganese (Mn) concentration in bean tissue were greater in bean monoculture than in grass intercropped beans. Bean monoculture also had greater soil NO3-N concentrations than grass intercropped treatments. In 2009, grass intercrops reduced dry bean yield >25% compared to bean monoculture. Annual ryegrass was the least competitive of the four annual grass species. This suggests that competition from grasses for nutrients, water, or light may have outweighed benefits accruing from grass intercropping. Additional studies are required to determine the appropriate grass and dry bean densities, as well as the optimum time of grass removal.

[Effects of intercropping Chinese onion cultivars of different allelopathic potential on cucumber growth and soil micro-environment].

PubMed

Yang, Yang; Wu, Feng-zhi

2011-10-01

A pot experiment was conducted to study the effects of intercropping various Chinese onion cultivars of different allelopathic potential on the cucumber growth and rhizospheric soil environment. When intercropped with high allelopathic Chinese onion cultivars, the EC value and peroxidase activity of cucumber rhizospheric soil decreased, while the pH value, invertase and catalase activities, and bacterial community diversity increased. The cloning and sequencing results indicated that most DGGE bands amplified from cucumber rhizospheric soil samples showed a high homology to uncultured bacterial species. The common bands were affiliated with Actinobacteria and Proteobacteria, and the differential bacteria bands were affiliated with Proteobacteria and Anaerolineaceae. Rhodospirillales and Acidobacteria were only found in the cucumber rhizospheric soil intercropped with low allelopathic Chinese onion cultivars. Correlation analysis showed that there were significant positive correlations between rhizospheric soil urease activity and cucumber seedlings height, total dry biomass, leaf area, and DGGE band number. It was suggested that intercropping high allelopathic Chinese onion cultivars could establish a good rhizospheric soil micro-environment for cucumber growth, and promote the growth of cucumber seedlings markedly.

Switchgrass (Panicum virgatum) Intercropping within Managed Loblolly Pine (Pinus taeda) Does Not Affect Wild Bee Communities.

PubMed

Campbell, Joshua W; Miller, Darren A; Martin, James A

2016-11-04

Intensively-managed pine ( Pinus spp.) have been shown to support diverse vertebrate communities, but their ability to support invertebrate communities, such as wild bees, has not been well-studied. Recently, researchers have examined intercropping switchgrass ( Panicum virgatum ), a native perennial, within intensively managed loblolly pine ( P. taeda ) plantations as a potential source for cellulosic biofuels. To better understand potential effects of intercropping on bee communities, we investigated visitation of bees within three replicates of four treatments of loblolly pine in Mississippi, U.S.A.: 3-4 year old pine plantations and 9-10 year old pine plantations with and without intercropped switchgrass. We used colored pan traps to capture bees during the growing seasons of 2013 and 2014. We captured 2507 bees comprised of 18 different genera during the two-year study, with Lasioglossum and Ceratina being the most common genera captured. Overall, bee abundances were dependent on plantation age and not presence of intercropping. Our data suggests that switchgrass does not negatively impact or promote bee communities within intensively-managed loblolly pine plantations.

Mapping Farming Practices in Belgian Intensive Cropping Systems from Sentinel-1 SAR Time Series

NASA Astrophysics Data System (ADS)

Chome, G.; Baret, P. V.; Defourny, P.

2016-08-01

The environmental impact of the so-called conventional farming system calls for new farming practices reducing negative externalities. Emerging farming practices such as no-till and new inter-cropping management are promising tracks. The development of methods to characterize crop management across an entire region and to understand their spatial dimension offers opportunities to accompany the transition towards a more sustainable agriculture.This research takes advantage of the unmatched polarimetric and temporal resolutions of Sentinel-1 SAR C- band to develop a method to identify farming practices at the parcel level. To this end, the detection of changes in backscattering due to surface roughness modification (tillage, inter-crop cover destruction ...) is used to detect the farming management. The final results are compared to a reference dataset collected through an intensive field campaign. Finally, the performances are discussed in the perspective of practices monitoring of cropping systems through remote sensing.

Efficiency of repeated phytoextraction of cadmium and zinc from an agricultural soil contaminated with sewage sludge.

PubMed

Luo, Kai; Ma, Tingting; Liu, Hongyan; Wu, Longhua; Ren, Jing; Nai, Fengjiao; Li, Rui; Chen, Like; Luo, Yongming; Christie, Peter

2015-01-01

Long-term application of sewage sludge resulted in soil cadmium (Cd) and zinc (Zn) contamination in a pot experiment conducted to phytoextract Cd/Zn repeatedly using Sedum plumbizincicola and Apium graceolens in monoculture or intercropping mode eight times. Shoot yields and soil physicochemical properties changed markedly with increasing number of remediation crops when the two plant species were intercropped compared with the unplanted control soil and the two monoculture treatments. Changes in soil microbial indices such as average well colour development, soil enzyme activity and soil microbial counts were also significantly affected by the growth of the remediation plants, especially intercropping with S. plumbizincicola and A. graveolens. The higher yields and amounts of Cd taken up indicated that intercropping of the hyperaccumulator and the vegetable species may be suitable for simultaneous agricultural production and soil remediation, with larger crop yields and higher phytoremediation efficiencies than under monoculture conditions.

Modeling Hydrological Services in Shade Grown Coffee Systems: Case Study of the Pico Duarte Region of the Dominican Republic

NASA Astrophysics Data System (ADS)

Erickson, J. D.; Gross, L.; Agosto Filion, N.; Bagstad, K.; Voigt, B. G.; Johnson, G.

2010-12-01

The modification of hydrologic systems in coffee-dominated landscapes varies widely according to the degree of shade trees incorporated in coffee farms. Compared to mono-cropping systems, shade coffee can produce both on- and off-farm benefits in the form of soil retention, moderation of sediment transport, and lower hydropower generating costs. The Pico Duarte Coffee Region and surrounding Madres de Las Aguas (Mother of Waters) Conservation Area in the Dominican Republic is emblematic of the challenges and opportunities of ecosystem service management in coffee landscapes. Shade coffee poly-cultures in the region play an essential role in ensuring ecosystem function to conserve water resources, as well as provide habitat for birds, sequester carbon, and provide consumptive resources to households. To model the provision, use, and flow of ecosystem services from coffee farms in the region, an application of the Artificial Intelligence for Ecosystem Services (ARIES) model was developed with particular focus on sediment regulation. ARIES incorporates an array of techniques from data mining, image analysis, neural networks, Bayesian statistics, information theory, and expert systems to model the production, delivery, and demand for ecosystem services. Geospatial data on slope, soils, and vegetation cover is combined with on-farm data collection of coffee production, tree diversity, and intercropping of household food. Given hydropower production and river recreation in the region, the management of sedimentation through on-farm practices has substantial, currently uncompensated value that has received recent attention as the foundation for a payment for ecosystem services system. Scenario analysis of the implications of agro-forestry management choices on farmer livelihoods and the multiple beneficiaries of farm-provided hydrological services provide a foundation for ongoing discussions in the region between local, national, and international interests.

[Effects of intercropping Sedum plumbizincicola in wheat growth season under wheat-rice rotation on the crops growth and their heavy metals uptake from different soil types].

PubMed

Zhao, Bing; Shen, Li-bo; Cheng, Miao-miao; Wang, Song-feng; Wu, Long-hua; Zhou, Shou-biao; Luo, Yong-ming

2011-10-01

A pot experiment with heavy metals- contaminated black soil from Heilongjiang Province, alluvial soil from Henan Province, and paddy soil from Zhejiang Province was conducted to study the effects of intercropping Sedum plumbizincicola in wheat growth season under wheat (Triticum aestivum) - rice (Oryza sativa) rotation on the growth of the crops and their heavy metals uptake, aimed to explore the feasibility of simultaneous grain production and heavy metals-contaminated soil phytoremediation in main food crop production areas of this country. Comparing with monoculture T. aestivum, intercropping S. plumbizincicola increased the soil NaNO3 -extractable Zn and Cd significantly, with the increment of extractable Zn in test paddy soil, alluvial soil, and black soil being 55%, 32% and 110%, and that of extractable Cd in test paddy soil and black soil being 38% and 110%, respectively. The heavy metals concentration in T. aestivum shoots under intercropping S. plumbizincicola was 0.1-0.9 times higher than that under monoculture T. aestivum, but the intercropping had little effects on the rice growth and its heavy metals uptake. Though the Cd concentration in rice grain after S. plumbizincicola planting was still higher than 0.2 mg kg(-1) (the limit of Cd in food standard), it presented a decreasing trend, as compared with that after monoculture T. aestivum. Therefore, intercropping S. plumbizincicola in wheat growth season under wheat-rice rota- tion could benefit the phytoremediation of heavy metals-contaminated soil, and decrease the food-chain risk of rotated rice.

[Environmental quality assessment of regional agro-ecosystem in Loess Plateau].

PubMed

Wang, Limei; Meng, Fanping; Zheng, Jiyong; Wang, Zhonglin

2004-03-01

Based on the detection and analysis of the contamination status of agro-ecosystem with apple-crops intercropping as the dominant cropping model in Loess Plateau, the individual factor and comprehensive environmental quality were assessed by multilevel fuzzy synthetic evaluation model, analytical hierarchy process(AHP), and improved standard weight deciding method. The results showed that the quality of soil, water and agricultural products was grade I, the social economical environmental quality was grade II, the ecological environmental quality was grade III, and the comprehensive environmental quality was grade I. The regional agro-ecosystem dominated by apple-crops intercropping was not the best model for the ecological benefits, but had the better social economical benefits.

Dataset on the abundance of ants and Cosmopolites sordidus damage in plantain fields with intercropped plants.

PubMed

Dassou, Anicet Gbèblonoudo; Carval, Dominique; Dépigny, Sylvain; Fansi, Gabriel; Tixier, Philippe

2016-12-01

The data presented in this article are related to the research article entitled "Ant abundance and Cosmopolites sordidus damage in plantain fields as affected by intercropping" (A.G. Dassou, D. Carval, S. Dépigny, G.H Fansi, P. Tixier, 2015) [1]. This article describes how associated crops maize (Zea mays), cocoyam (Xanthosoma sagittifolium) and bottle gourd (Lagenaria siceraria) intercropped in the plantain fields in Cameroun modify ant community structure and damages of banana weevil Cosmopolites sordidus. The field data set is made publicly available to enable critical or extended analyzes.

Agronomy of strip intercropping broccoli with alyssum for biological control of aphids

USDA-ARS?s Scientific Manuscript database

Organic broccoli growers in California typically control aphids by intercropping broccoli with strips of alyssum (Lobularia maritima (L.) Desv.) which attracts hoverflies (Diptera: Syrphidae) that are important predators of aphids. A three year study with transplanted organic broccoli in Salinas, ...

Agroforestry leads to shifts within the gammaproteobacterial microbiome of banana plants cultivated in Central America

PubMed Central

Köberl, Martina; Dita, Miguel; Martinuz, Alfonso; Staver, Charles; Berg, Gabriele

2015-01-01

Bananas (Musa spp.) belong to the most important global food commodities, and their cultivation represents the world's largest monoculture. Although the plant-associated microbiome has substantial influence on plant growth and health, there is a lack of knowledge of the banana microbiome and its influencing factors. We studied the impact of (i) biogeography, and (ii) agroforestry on the banana-associated gammaproteobacterial microbiome analyzing plants grown in smallholder farms in Nicaragua and Costa Rica. Profiles of 16S rRNA genes revealed high abundances of Pseudomonadales, Enterobacteriales, Xanthomonadales, and Legionellales. An extraordinary high diversity of the gammaproteobacterial microbiota was observed within the endophytic microenvironments (endorhiza and pseudostem), which was similar in both countries. Enterobacteria were identified as dominant group of above-ground plant parts (pseudostem and leaves). Neither biogeography nor agroforestry showed a statistically significant impact on the gammaproteobacterial banana microbiome in general. However, indicator species for each microenvironment and country, as well as for plants grown in Coffea intercropping systems with and without agri-silvicultural production of different Fabaceae trees (Inga spp. in Nicaragua and Erythrina poeppigiana in Costa Rica) could be identified. For example, banana plants grown in agroforestry systems were characterized by an increase of potential plant-beneficial bacteria, like Pseudomonas and Stenotrophomonas, and on the other side by a decrease of Erwinia. Hence, this study could show that as a result of legume-based agroforestry the indigenous banana-associated gammaproteobacterial community noticeably shifted. PMID:25717322

Agroforestry leads to shifts within the gammaproteobacterial microbiome of banana plants cultivated in Central America.

PubMed

Köberl, Martina; Dita, Miguel; Martinuz, Alfonso; Staver, Charles; Berg, Gabriele

2015-01-01

Bananas (Musa spp.) belong to the most important global food commodities, and their cultivation represents the world's largest monoculture. Although the plant-associated microbiome has substantial influence on plant growth and health, there is a lack of knowledge of the banana microbiome and its influencing factors. We studied the impact of (i) biogeography, and (ii) agroforestry on the banana-associated gammaproteobacterial microbiome analyzing plants grown in smallholder farms in Nicaragua and Costa Rica. Profiles of 16S rRNA genes revealed high abundances of Pseudomonadales, Enterobacteriales, Xanthomonadales, and Legionellales. An extraordinary high diversity of the gammaproteobacterial microbiota was observed within the endophytic microenvironments (endorhiza and pseudostem), which was similar in both countries. Enterobacteria were identified as dominant group of above-ground plant parts (pseudostem and leaves). Neither biogeography nor agroforestry showed a statistically significant impact on the gammaproteobacterial banana microbiome in general. However, indicator species for each microenvironment and country, as well as for plants grown in Coffea intercropping systems with and without agri-silvicultural production of different Fabaceae trees (Inga spp. in Nicaragua and Erythrina poeppigiana in Costa Rica) could be identified. For example, banana plants grown in agroforestry systems were characterized by an increase of potential plant-beneficial bacteria, like Pseudomonas and Stenotrophomonas, and on the other side by a decrease of Erwinia. Hence, this study could show that as a result of legume-based agroforestry the indigenous banana-associated gammaproteobacterial community noticeably shifted.

Phytoremediation of soil contaminated with cadmium, copper and polychlorinated biphenyls.

PubMed

Wu, Longhua; Li, Zhu; Han, Cunliang; Liu, Ling; Teng, Ying; Sun, Xianghui; Pan, Cheng; Huang, Yujuan; Luo, Yongming; Christie, Peter

2012-07-01

A pot experiment and afield trial were conducted to study the remediation of an aged field soil contaminated with cadmium, copper and polychlorinated biphenyls (PCBs) (7.67 +/- 0.51 mg kg(-1) Cd, 369 +/- 1 mg kg(-1) Cu in pot experiment; 8.46 +/- 0.31 mg kg(-1) Cd, 468 +/- 7 mg kg(-1) Cu, 323 +/- 12 microg kg(-1) PCBs for field experiment) under different cropping patterns. In the pot experiment Sedum plumbizincicola showed pronounced Cd phytoextraction. After two periods (14 months) of cropping the Cd removal rates in these two treatments were 52.2 +/- 12.0 and 56.1 +/- 9.1%, respectively. Total soil PCBs in unplanted control pots decreased from 323 +/- 11 to 49.3 +/- 6.6 microg kg(-1), but with no significant difference between treatments. The field microcosm experiment intercropping of three plant species reduced the yield of S. plumbizincicola, with a consequent decrease in soil Cd removal. S. plumbizincicola intercropped with E. splendens had the highest shoot Cd uptake (18.5 +/- 1.8 mg pot(-1)) after 6 months planting followed by intercropping with M. sativa (15.9 +/- 1.9 mg pot(-1)). Liming with S. plumbizincicola intercropped with M. sativa significantly promoted soil PCB degradation by 25.2%. Thus, adjustment of soil pH to 5.56 combined with intercropping with S. plumbizincicola and M. sativagave high removal rates of Cd, Cu, and PCBs.

Chinese chives and garlic in intercropping in strawberry high tunnels for Neopamera bilobata Say (Hemiptera: Rhyparochromidae) control.

PubMed

Hata, F T; Ventura, M U; Béga, V L; Camacho, I M; de Paula, M T

2018-05-08

Strawberry is affected by several pests and diseases. Neopamera bilobata is an emerging pest that has been reported by several strawberry growers, usually associated with catfacing symptoms in fruits. We evaluated intercropping garlic or Chinese chives on N. bilobata populations on strawberry crops grown in high tunnels in two experiments. In the first experiment, we evaluated N. bilobata populations on strawberry intercropping with garlic plants (three densities: 8, 16, 24 GP - garlic plant per plot) on the bags by taking 12 samples from December 2015 to April 2017. N. bilobata populations on strawberry were also assessed when Chinese chives were grown under the suspended wooden structures in which strawberry plants are grown ('undercropping') (14 samples), in two high tunnels, from November 2016 to March 2017. The number of nymphs and adults on 14 randomly selected fruits per plot were assessed. During the garlic intercropping experiment, the treatments of three densities of garlic reduced N. bilobata populations; however, the 24 GP treatment caused a greater reduction than the 8 GP treatment. Garlic densities reduced N. bilobata populations by 35, 50, and 64% for the 8, 16, and 24 GP treatments, respectively. Chinese chives cultivated under the structures reduced N. bilobata populations by 47%. The results suggest that intercropping garlic or undercropping Chinese chives are suitable tools to be tested in integrated pest management in strawberry crops.

[Effect of agroforestry model on inhibition of Oncomelania snails in plateau mountainous area of Yunnan Province].

PubMed

Zhang, Chun-Hua; Tang, Guo-Yong; Liu, Fang-Yan; Li, Kun

2012-10-01

To evaluate the effect of agroforestry models on the inhibition of Oncomelania snails in the plateau mountainous area of Yunnan Province. The experimental field was established at Sanying Village of Eryuan County, Yunnan Province, where the "Flourishing Forest and Controlling Snails Project" was implemented. Different drought crops (alfalfa, vegetables, broad bean, garlic, lettuce, celery, green onions, and wheat) were intercropped under walnut forest in experimental groups, and the crops were not intercropped under walnut forest in a control group. The growth of forest, the change of snails and short-term income of residents were investigated. Agroforestry models promoted the forestry growth and effectively inhibited the growth of snails. There was a little snail in one of the experimental group that forest was intercropped with alfalfa (the occurrence rate of frames with living snails was 3.33%, the average density of living snails was 0.004/0.1 m2, and the declining rates were both 50.00%). The snails were not found in other intercropped models. The income of residents in the experimental groups increased (900-6 800 Yuan per year) compared with that in the control group. The model of walnut forest intercropped with crops not only has the obvious effect on inhibition of snails, but also has good economic and ecological benefits in the plateau mountainous area of Yunnan Province.

Spatial arrangement, population density and legume species effect of yield of forage sorghum-legume intercropping

USDA-ARS?s Scientific Manuscript database

Sorghum (Sorghum bicolor) is a stress tolerant forage crop grown extensively in the Southern High Plains. However, sorghum forage quality is lower than that of corn. Intercropping sorghum with legumes can improve quality and productivity of forage. However, tall statured sorghum limits the resources...

Effect of plant density and mixing ratio on crop yield in sweet corn/mungbean intercropping.

PubMed

Sarlak, S; Aghaalikhani, M; Zand, B

2008-09-01

In order to evaluate the ear and forage yield of sweet corn (Zea mays L. var. Saccarata) in pure stand and intercropped with mung bean (Vigna radiata L.), a field experiment was conducted at Varamin region on summer 2006. Experiment was carried out in a split plot design based on randomized complete blocks with 4 replications. Plant density with 3 levels [Low (D1), Mean (D2) and High (D3) respecting 6, 8 and 10 m(-2) for sweet corn, cultivar S.C.403 and 10, 20 and 30 m(-2) for mung bean cultivar, Partow] was arranged in main plots and 5 mixing ratios [(P1) = 0/100, (P2) = 25/75, (P3) = 50/50, (P4) = 75/25, (P5) = 100/0% for sweet corn/mung bean, respectively] were arranged in subplots. Quantitative attributes such as plant height, sucker numbers, LER, dry matter distribution in different plant organs were measured in sweet corn economical maturity. Furthermore the yield of cannable ear corn and yield components of sweet corn and mung bean were investigated. Results showed that plant density has not any significant effect on evaluated traits, while the effect of mixing ratio was significant (p < 0.01). Therefore, the mixing ratio of 75/25 (sweet corn/mung bean) could be introduced as the superior mixing ratio; because of it's maximum rate of total sweet corn's biomass, forage yield, yield and yield components of ear corn in intercropping. Regarding to profitability indices of intercropping, the mixing ratio 75/25 (sweet corn/mung bean) in low density (D1P2) which showed the LER = 1.03 and 1.09 for total crop yield before ear harvesting and total forage yield after ear harvest respectively, was better than corn or mung bean monoculture.

Intercropping Corn with Lablab bean, Velvet Bean, and Scarlet Runner Bean for Forage

USDA-ARS?s Scientific Manuscript database

Low crude protein (CP) concentration in corn (Zea mays L.) forage is its major limitation in dairy rations. This experiment was designed to determine if intercropping corn with climbing beans is a viable option to increase CP concentration in forage rather than purchasing costly CP supplements for ...

Impacts of human-related practices on Ommatissus lybicus infestations of date palm in Oman.

PubMed

Al-Kindi, Khalifa M; Kwan, Paul; Andrew, Nigel R; Welch, Mitchell

2017-01-01

Date palm cultivation is economically important in the Sultanate of Oman, with significant financial investments coming from both the government and private individuals. However, a widespread Dubas bug (DB) (Ommatissus lybicus Bergevin) infestation has impacted regions including the Middle East, North Africa, Southeast Russia, and Spain, resulting in widespread damages to date palms. In this study, techniques in spatial statistics including ordinary least squares (OLS), geographically weighted regression (GRW), and exploratory regression (ER) were applied to (a) model the correlation between DB infestations and human-related practices that include irrigation methods, row spacing, palm tree density, and management of undercover and intercropped vegetation, and (b) predict the locations of future DB infestations in northern Oman. Firstly, we extracted row spacing and palm tree density information from remote sensed satellite images. Secondly, we collected data on irrigation practices and management by using a simple questionnaire, augmented with spatial data. Thirdly, we conducted our statistical analyses using all possible combinations of values over a given set of candidate variables using the chosen predictive modelling and regression techniques. Lastly, we identified the combination of human-related practices that are most conducive to the survival and spread of DB. Our results show that there was a strong correlation between DB infestations and several human-related practices parameters (R2 = 0.70). Variables including palm tree density, spacing between trees (less than 5 x 5 m), insecticide application, date palm and farm service (pruning, dethroning, remove weeds, and thinning), irrigation systems, offshoots removal, fertilisation and labour (non-educated) issues, were all found to significantly influence the degree of DB infestations. This study is expected to help reduce the extent and cost of aerial and ground sprayings, while facilitating the allocation of date palm plantations. An integrated pest management (IPM) system monitoring DB infestations, driven by GIS and remote sensed data collections and spatial statistical models, will allow for an effective DB management program in Oman. This will in turn ensure the competitiveness of Oman in the global date fruits market and help preserve national yields.

Morphological plasticity in watermelon in response to interspecific competition in a low-resource intercropping system

USDA-ARS?s Scientific Manuscript database

Interspecies specific interactions are generally regarded as drivers of plant productivity in multispecies agroecosystems. Positive interactions such as facilitation can dominate over competition under high abiotic stress conditions. Furthermore, complementary use of resource in diverse communities ...

Crop root behavior coordinates phosphorus status and neighbors: from field studies to three-dimensional in situ reconstruction of root system architecture.

PubMed

Fang, Suqin; Gao, Xiang; Deng, Yan; Chen, Xinping; Liao, Hong

2011-03-01

Root is a primary organ to respond to environmental stimuli and percept signals from neighboring plants. In this study, root responses in maize (Zea mays)/soybean (Glycine max) intercropping systems recognized soil phosphorus (P) status and neighboring plants in the field. Compared to self culture, the maize variety GZ1 intercropping with soybean HX3 grew much better on low P, but not in another maize variety, NE1. This genotypic response decreased with increasing distance between plants, suggesting that root interactions were important. We further conducted a detailed and quantitative study of root behavior in situ using a gel system to reconstruct the three-dimensional root architecture. The results showed that plant roots could integrate information on P status and root behavior of neighboring plants. When intercropped with its kin, maize or soybean roots grew close to each other. However, when maize GZ1 was grown with soybean HX3, the roots on each plant tended to avoid each other and became shallower on stratified P supply, but not found with maize NE1. Furthermore, root behavior in gel was highly correlated to shoot biomass and P content for field-grown plants grown in close proximity. This study provides new insights into the dynamics and complexity of root behavior and kin recognition among crop species in response to nutrient status and neighboring plants. These findings also indicate that root behavior not only depends on neighbor recognition but also on a coordinated response to soil P status, which could be the underlying cause for the different growth responses in the field.

Crop biomass not species richness drives weed suppression in warm-season annual grass-legume intercrops in the Northeast

USDA-ARS?s Scientific Manuscript database

Intercropping with functionally diverse crops can reduce the availability of resources that could otherwise be used by weeds. An experiment was conducted six times across the northeastern United States in 2013 and 2014 to examine the effects of functional diversity and species richness on weed suppr...

[Effects of reduced nitrogen application and soybean intercropping on nitrogen balance of sugarcane field].

PubMed

Liu, Yu; Zhang, Ying; Yang, Wen-ting; Li, Zhi-xian; Guan, Ao-mei

2015-03-01

A four-year (2010-2013) field experiment was carried out to explore the effects of three planting patterns (sugarcane, soybean monoculture and sugarcane-soybean 1:2 intercropping) with two nitrogen input levels (300 and 525 kg . hm-2) on soybean nitrogen fixation, sugarcane and soybean nitrogen accumulation, and ammonia volatilization and nitrogen leaching in sugarcane field. The results showed that the soybean nitrogen fixation efficiency (NFE) of sugarcane-soybean inter-cropping was lower than that of soybean monoculture. There was no significant difference in NFE among the treatments with the two nitrogen application rates. The nitrogen application rate and inter-cropping did not remarkably affect nitrogen accumulation of sugarcane and soybean. The ammonia volatilization of the reduced nitrogen input treatment was significantly lower than that of the conventional nitrogen input treatment. Furthermore, there was no significant difference in nitrogen leaching at different nitrogen input levels and among different planting patterns. The sugarcane field nitrogen balance analysis indicated that the nitrogen application rate dominated the nitrogen budget of sugarcane field. During the four-year experiment, all treatments leaved a nitrogen surplus (from 73.10 to 400.03 kg . hm-2) , except a nitrogen deficit of 66.22 kg . hm-2 in 2011 in the treatment of sugarcane monoculture with the reduced nitrogen application. The excessive nitrogen surplus might increase the risk of nitrogen pollution in the field. In conclusion, sugarcane-soybean intercropping with reduced nitrogen application is feasible to practice in consideration of enriching the soil fertility, reducing nitrogen pollution and saving production cost in sugarcane field.

Conservation Agriculture Improves Soil Quality, Crop Yield, and Incomes of Smallholder Farmers in North Western Ghana

PubMed Central

Naab, Jesse B.; Mahama, George Y.; Yahaya, Iddrisu; Prasad, P. V. V.

2017-01-01

Conservation agriculture (CA) practices are being widely promoted in many areas in sub-Saharan Africa to recuperate degraded soils and improve ecosystem services. This study examined the effects of three tillage practices [conventional moldboard plowing (CT), hand hoeing (MT) and no-tillage (NT)], and three cropping systems (continuous maize, soybean–maize annual rotation, and soybean/maize intercropping) on soil quality, crop productivity, and profitability in researcher and farmer managed on-farm trials from 2010 to 2013 in northwestern Ghana. In the researcher managed mother trial, the CA practices of NT, residue retention and crop rotation/intercropping maintained higher soil organic carbon, and total soil N compared to conventional tillage practices after 4 years. Soil bulk density was higher under NT than under CT soils in the researcher managed mother trails or farmers managed baby trials after 4 years. In the researcher managed mother trial, there was no significant difference between tillage systems or cropping systems in maize or soybean yields in the first three seasons. In the fourth season, crop rotation had the greatest impact on maize yields with CT maize following soybean increasing yields by 41 and 49% compared to MT and NT maize, respectively. In the farmers’ managed trials, maize yield ranged from 520 to 2700 kg ha-1 and 300 to 2000 kg ha-1 for CT and NT, respectively, reflecting differences in experience of farmers with NT. Averaged across farmers, CT cropping systems increased maize and soybean yield ranging from 23 to 39% compared with NT cropping systems. Partial budget analysis showed that the cost of producing maize or soybean is 20–29% cheaper with NT systems and gives higher returns to labor compared to CT practice. Benefit-to-cost ratios also show that NT cropping systems are more profitable than CT systems. We conclude that with time, implementation of CA practices involving NT, crop rotation, intercropping of maize and soybean along with crop residue retention presents a win–win scenario due to improved crop yield, increased economic return, and trends of increasing soil fertility. The biggest challenge, however, remains with producing enough biomass and retaining same on the field. PMID:28680427

Energizing marginal soils: A perennial cropping system for Sida hermaphrodita

NASA Astrophysics Data System (ADS)

Nabel, Moritz; Poorter, Hendrik; Temperton, Vicky; Schrey, Silvia D.; Koller, Robert; Schurr, Ulrich; Jablonowski, Nicolai D.

2017-04-01

As a way to avoid land use conflicts, the use of marginal soils for the production of plant biomass can be a sustainable alternative to conventional biomass production (e.g. maize). However, new cropping strategies have to be found that meet the challenge of crop production under marginal soil conditions. We aim for increased soil fertility by the use of the perennial crop Sida hermaphrodita in combination with organic fertilization and legume intercropping to produce substantial biomass yield. We present results of a three-year outdoor mesocosm experiment testing the perennial energy crop Sida hermaphrodita grown on a marginal model substrate (sand) with four kinds of fertilization (Digestate broadcast, Digestate Depot, mineral NPK and unfertilized control) in combination with legume intercropping. After three years, organic fertilization (via biogas digestate) compared to mineral fertilization (NPK), reduced the nitrate concentration in leachate and increased the soil carbon content. Biomass yields of Sida were 25% higher when fertilized organically, compared to mineral fertilizer. In general, digestate broadcast application reduced root growth and the wettability of the sandy substrate. However, when digestate was applied locally as depot to the rhizosphere, root growth increased and the wettability of the sandy substrate was preserved. Depot fertilization increased biomass yield by 10% compared to digestate broadcast fertilization. We intercropped Sida with various legumes (Trifolium repens, Trifolium pratense, Melilotus spp. and Medicago sativa) to enable biological nitrogen fixation and make the cropping system independent from synthetically produced fertilizers. We could show that Medicago sativa grown on marginal substrate fixed large amounts of N, especially when fertilized organically, whereas mineral fertilization suppressed biological nitrogen fixation. We conclude that the perennial energy crop Sida in combination with organic fertilization has great potential to increase the soil fertility of marginal substrates and produce substantial biomass yields.

Effects of intercropping of oat (Avena sativa L.) with white lupin (Lupinus albus L.) on the mobility of target elements for phytoremediation and phytomining in soil solution.

PubMed

Wiche, Oliver; Székely, Balazs; Kummer, Nicolai-Alexeji; Moschner, Christin; Heilmeier, Hermann

2016-09-01

This study aims to investigate how intercropping of oat (Avena sativa L.) with white lupin (Lupinus albus L.) affects the mobile fractions of trace metals (Fe, Mn, Pb, Cd, Th, U, Sc, La, Nd, Ge) in soil solution. Oat and white lupin were cultivated in monocultures and mixed cultures with differing oat/white lupin ratios (11% and 33% lupin, respectively). Temporal variation of soil solution chemistry was compared with the mobilization of elements in the rhizosphere of white lupin and concentrations in plant tissues. Relative to the monocrops, intercropping of oat with 11% white lupin significantly increased the concentrations of Fe, Pb, Th, La and Nd in soil solution as well as the concentrations of Fe, Pb, Th, Sc, La and Nd in tissues of oat. Enhanced mobility of the mentioned elements corresponded to a depletion of elements in the rhizosphere soil of white lupin. In mixed cultures with 33% lupin, concentrations in soil solution only slightly increased. We conclude that intercropping with 11% white lupin might be a promising tool for phytoremediation and phytomining research enhancing mobility of essential trace metals as well as elements with relevance for phytoremediation (Pb, Th) and phytomining (La, Nd, Sc) in soil.

Nutrient Exchange through Hyphae in Intercropping Systems Affects Yields

ERIC Educational Resources Information Center

Thun, Tim Von

2013-01-01

Arbuscular mycorrhizae fungi (AMF) play a large role in the current understanding of the soil ecosystem. They increase nutrient and water uptake, improve soil structure, and form complex hyphal networks that transfer nutrients between plants within an ecosystem. Factors such as species present, the physiological balance between the plants in the…

Intercropping of two Leucaena spp. with sweet potato: yield, growth rate and biomass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swift, J.F.

1982-01-01

Results of trials with Leucaena leucocephala and Leucaena diversifolia at Wau, Papua New Guinea, showed potential benefits of the agroforestry cropping system. The total biomass yield (sweet potato plus firewood and green manure) was considerably greater than the yield per unit area of sweet potato alone. 3 references.

Evaluation of intercropped switchgrass establishment under a range of experimental site preparation treatments in a forested setting on the Lower Coastal Plain of North Carolina, U.S.A

Treesearch

Janine M. Albaugh; Eric B. Sucre; Zakiya H. Leggett; Jean-Christophe Domec; John S. King

2012-01-01

There is growing interest in using switchgrass (Panicum virgatum L.) as a biofuel crop and for its potential to sequester carbon. However, there are limited data on the establishment success of this species when grown as a forest intercrop in coastal plain settings of the U.S. Southeast. Therefore, we studied establishment success of switchgrass...

Conservation agriculture among small scale farmers in semi-arid region of Kenya does improve soil biological quality and soil organic carbon

NASA Astrophysics Data System (ADS)

Waweru, Geofrey; Okoba, Barrack; Cornelis, Wim

2016-04-01

The low food production in Sub-Saharan Africa (SSA) has been attributed to declining soil quality. This is due to soil degradation and fertility depletion resulting from unsustainable conventional farming practices such as continuous tillage, crop residue burning and mono cropping. To overcome these challenges, conservation agriculture (CA) is actively promoted. However, little has been done in evaluating the effect of each of the three principles of CA namely: minimum soil disturbance, maximum surface cover and diversified/crop rotation on soil quality in SSA. A study was conducted for three years from 2012 to 2015 in Laikipia East sub county in Kenya to evaluate the effect of tillage, surface cover and intercropping on a wide variety of physical, chemical and biological soil quality indicators, crop parameters and the field-water balance. This abstract reports on soil microbial biomass carbon (SMBC) and soil organic carbon (SOC). The experimental set up was a split plot design with tillage as main treatment (conventional till (CT), no-till (NT) and no-till with herbicide (NTH)), and intercropping and surface cover as sub treatment (intercropping maize with: beans, MB; beans and leucaena, MBL; beans and maize residues at 1.5 Mg ha-1 MBMu, and dolichos, MD). NT had significantly higher SMBC by 66 and 31% compared with CT and NTH respectively. SOC was significantly higher in NTH than CT and NT by 15 and 4%, respectively. Intercropping and mulching had significant effect on SMBC and SOC. MBMu resulted in higher SMBC by 31, 38 and 43%, and SOC by 9, 20 and 22% as compared with MBL, MD and MB, respectively. SMBC and SOC were significantly affected by the interaction between tillage, intercropping and soil cover with NTMBMu and NTHMBMu having the highest SMBC and SOC, respectively. We conclude that indeed tillage, intercropping and mulching substantially affect SMBC and SOC. On the individual components of CA, tillage and surface cover had the highest effect on SMBC and SOC, respectively, but the highest positive effect was realized when all the three principles were applied consecutively. Therefore, CA has the potential to improve biological soil quality among small scale rainfed farmers and thus promote sustainable production.

Tree Plantation Systems Influence Nitrogen Retention and the Abundance of Nitrogen Functional Genes in the Solomon Islands

PubMed Central

Reverchon, Frédérique; Bai, Shahla H.; Liu, Xian; Blumfield, Timothy J.

2015-01-01

Tree mono-plantations are susceptible to soil nutrient impoverishment and mixed species plantations have been proposed as a way of maintaining soil fertility while enhancing biodiversity. In the Solomon Islands, mixed species plantations where teak (Tectona grandis) is inter-planted with a local tree species (Flueggea flexuosa) have been used as an alternative to teak mono-plantations and are expected to increase soil microbial diversity and modify microbial biogeochemical processes. In this study, we quantified the abundance of microbial functional genes involved in the nitrogen (N) cycle from soil samples collected in teak, flueggea, and mixed species plantations. Furthermore, we measured soil properties such as pH, total carbon (C) and total N, stable N isotope composition (δ15N), and inorganic N pools. Soil pH and δ15N were higher under teak than under flueggea, which indicates that intercropping teak with flueggea may decrease bacterial activities and potential N losses. Higher C:N ratios were found under mixed species plantations than those under teak, suggesting an enhancement of N immobilization that would help preventing fast N losses. However, inorganic N pools remained unaffected by plant cover. Inter-planting teak with flueggea in mixed species plantations generally increased the relative abundance of denitrification genes and promoted the enrichment of nosZ-harboring denitrifiers. However, it reduced the abundance of bacterial amoA (ammonia monooxygenase) genes compared to teak mono-plantations. The abundance of most denitrification genes correlated with soil total N and C:N ratio, while bacterial and archeal nitrification genes correlated positively with soil NH4+ concentrations. Altogether, these results show that the abundance of bacterial N-cycling functional guilds vary under teak and under mixed species plantations, and that inter-planting teak with flueggea may potentially alleviate N losses associated with nitrification and denitrification and favor N retention. Mixed plantations could also allow an increase in soil C and N stocks without losing the source of income that teak trees represent for local communities. PMID:26733978

[Analysis on difference of richness of traditional Chinese medicine resources in Chongqing based on grid technology].

PubMed

Zhang, Xiao-Bo; Qu, Xian-You; Li, Meng; Wang, Hui; Jing, Zhi-Xian; Liu, Xiang; Zhang, Zhi-Wei; Guo, Lan-Ping; Huang, Lu-Qi

2017-11-01

After the end of the national and local medicine resources census work, a large number of Chinese medicine resources and distribution of data will be summarized. The species richness between the regions is a valid indicator for objective reflection of inter-regional resources of Chinese medicine. Due to the large difference in the size of the county area, the assessment of the intercropping of the resources of the traditional Chinese medicine by the county as a statistical unit will lead to the deviation of the regional abundance statistics. Based on the rule grid or grid statistical methods, the size of the statistical unit due to different can be reduced, the differences in the richness of traditional Chinese medicine resources are caused. Taking Chongqing as an example, based on the existing survey data, the difference of richness of traditional Chinese medicine resources under different grid scale were compared and analyzed. The results showed that the 30 km grid could be selected and the richness of Chinese medicine resources in Chongqing could reflect the objective situation of intercropping resources richness in traditional Chinese medicine better. Copyright© by the Chinese Pharmaceutical Association.

Yield performance and bean quality traits of cacao propagated by grafting and somatic embryo-derived cuttings

USDA-ARS?s Scientific Manuscript database

Cacao (Theobroma cacao) has great potential as a component of a small tropical farming system. It adapts to a wide range of soils of climatic conditions, grows well under minimum tillage, adapts to temporary intercropping, has the potential of being sold in local and export markets and the pods are ...

Microbial nitrogen cycling response to forest-based bioenergy production.

PubMed

Minick, Kevan J; Strahm, Brian D; Fox, Thomas R; Sucre, Eric B; Leggett, Zakiya H

2015-12-01

Concern over rising atmospheric CO2 and other greenhouse gases due to fossil fuel combustion has intensified research into carbon-neutral energy production. Approximately 15.8 million ha of pine plantations exist across the southeastern United States, representing a vast land area advantageous for bioenergy production without significant landuse change or diversion of agricultural resources from food production. Furthermore, intercropping of pine with bioenergy grasses could provide annually harvestable, lignocellulosic biomass feedstocks along with production of traditional wood products. Viability of such a system hinges in part on soil nitrogen (N) availability and effects of N competition between pines and grasses on ecosystem productivity. We investigated effects of intercropping loblolly pine (Pinus taeda) with switchgrass (Panicum virgatum) on microbial N cycling processes in the Lower Coastal Plain of North Carolina, USA. Soil samples were collected from bedded rows of pine and interbed space of two treatments, composed of either volunteer native woody and herbaceous vegetation (pine-native) or pure switchgrass (pine-switchgrass) in interbeds. An in vitro 15N pool-dilution technique was employed to quantify gross N transformations at two soil depths (0-5 and 5-15 cm) on four dates in 2012-2013. At the 0-5 cm depth in beds of the pine-switchgrass treatment, gross N mineralization was two to three times higher in November and February compared to the pine-native treatment, resulting in increased NH4(+) availability. Gross and net nitrification were also significantly higher in February in the same pine beds. In interbeds of the pine-switchgrass treatment, gross N mineralization was lower from April to November, but higher in February, potentially reflecting positive effects of switchgrass root-derived C inputs during dormancy on microbial activity. These findings indicate soil N cycling and availability has increased in pine beds of the pine-switchgrass treatment compared to those of the pine-native treatment, potentially alleviating any negative effects of N competition between pine and switchgrass. We expect that reduced soil C in the pine-switchgrass treatment, effects of pine and switchgrass rooting on soil C availability, and plant N demand are major factors influencing soil N transformations. Future research should examine rooting architecture in-intercropped systems and the effects on soil microbial communities and function.

Acid phosphatase role in chickpea/maize intercropping.

PubMed

Li, S M; Li, L; Zhang, F S; Tang, C

2004-08-01

Organic P comprises 30-80 % of the total P in most agricultural soils. It has been proven that chickpea facilitates P uptake from an organic P source by intercropped wheat. In this study, acid phosphatase excreted from chickpea roots is quantified and the contribution of acid phosphatase to the facilitation of P uptake by intercropped maize receiving phytate is examined. For the first experiment using hydroponics, maize (Zea mays 'Zhongdan No. 2') and chickpea (Cicer arietinum 'Sona') were grown in either the same or separate containers, and P was supplied as phytate, KH2PO4 at 0.25 mmol P L(-1), or not at all. The second experiment involved soil culture with three types of root separation between the two species: (1) plastic sheet, (2) nylon mesh, and (3) no barrier. Maize plants were grown in one compartment and chickpea in the other. Phosphorus was supplied as phytate, Ca(H2PO4)2 at 50 mg P kg(-1), or no P added. In the hydroponics study, the total P uptake by intercropped maize supplied with phytate was 2.1-fold greater than when it was grown as a monoculture. In the soil experiment, when supplied with phytate, total P uptake by maize with mesh barrier and without root barrier was 2.2 and 1.5 times, respectively, as much as that with solid barrier. In both experiments, roots of both maize and chickpea supplied with phytate and no P secreted more acid phosphatase than those with KH2PO4 or Ca(H2PO4)2. However, average acid phosphatase activity of chickpea roots supplied with phytate was 2-3-fold as much as maize. Soil acid phosphatase activity in the rhizosphere of chickpea was also significantly higher than maize regardless of P sources. Chickpea can mobilize organic P in both hydroponic and soil cultures, leading to an interspecific facilitation in utilization of organic P in maize/chickpea intercropping.

Proteomic Analysis of the Relationship between Metabolism and Nonhost Resistance in Soybean Exposed to Bipolaris maydis.

PubMed

Dong, Yumei; Su, Yuan; Yu, Ping; Yang, Min; Zhu, Shusheng; Mei, Xinyue; He, Xiahong; Pan, Manhua; Zhu, Youyong; Li, Chengyun

2015-01-01

Nonhost resistance (NHR) pertains to the most common form of plant resistance against pathogenic microorganisms of other species. Bipolaris maydis is a non-adapted pathogen affecting soybeans, particularly of maize/soybean intercropping systems. However, no experimental evidence has described the immune response of soybeans against B. maydis. To elucidate the molecular mechanism underlying NHR in soybeans, proteomics analysis based on two-dimensional polyacrylamide gel electrophoresis (2-DE) was performed to identify proteins involved in the soybean response to B. maydis. The spread of B. maydis spores across soybean leaves induced NHR throughout the plant, which mobilized almost all organelles and various metabolic processes in response to B. maydis. Some enzymes, including ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), mitochondrial processing peptidase (MPP), oxygen evolving enhancer (OEE), and nucleoside diphosphate kinase (NDKs), were found to be related to NHR in soybeans. These enzymes have been identified in previous studies, and STRING analysis showed that most of the protein functions related to major metabolic processes were induced as a response to B. maydis, which suggested an array of complex interactions between soybeans and B. maydis. These findings suggest a systematic NHR against non-adapted pathogens in soybeans. This response was characterized by an overlap between metabolic processes and response to stimulus. Several metabolic processes provide the soybean with innate immunity to the non-adapted pathogen, B. maydis. This research investigation on NHR in soybeans may foster a better understanding of plant innate immunity, as well as the interactions between plant and non-adapted pathogens in intercropping systems.

Proteomic Analysis of the Relationship between Metabolism and Nonhost Resistance in Soybean Exposed to Bipolaris maydis

PubMed Central

Dong, Yumei; Su, Yuan; Yu, Ping; Yang, Min; Zhu, Shusheng; Mei, Xinyue; He, Xiahong; Pan, Manhua; Zhu, Youyong; Li, Chengyun

2015-01-01

Nonhost resistance (NHR) pertains to the most common form of plant resistance against pathogenic microorganisms of other species. Bipolaris maydis is a non-adapted pathogen affecting soybeans, particularly of maize/soybean intercropping systems. However, no experimental evidence has described the immune response of soybeans against B. maydis. To elucidate the molecular mechanism underlying NHR in soybeans, proteomics analysis based on two-dimensional polyacrylamide gel electrophoresis (2-DE) was performed to identify proteins involved in the soybean response to B. maydis. The spread of B. maydis spores across soybean leaves induced NHR throughout the plant, which mobilized almost all organelles and various metabolic processes in response to B. maydis. Some enzymes, including ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), mitochondrial processing peptidase (MPP), oxygen evolving enhancer (OEE), and nucleoside diphosphate kinase (NDKs), were found to be related to NHR in soybeans. These enzymes have been identified in previous studies, and STRING analysis showed that most of the protein functions related to major metabolic processes were induced as a response to B. maydis, which suggested an array of complex interactions between soybeans and B. maydis. These findings suggest a systematic NHR against non-adapted pathogens in soybeans. This response was characterized by an overlap between metabolic processes and response to stimulus. Several metabolic processes provide the soybean with innate immunity to the non-adapted pathogen, B. maydis. This research investigation on NHR in soybeans may foster a better understanding of plant innate immunity, as well as the interactions between plant and non-adapted pathogens in intercropping systems. PMID:26513657

Research on complex 3D tree modeling based on L-system

NASA Astrophysics Data System (ADS)

Gang, Chen; Bin, Chen; Yuming, Liu; Hui, Li

2018-03-01

L-system as a fractal iterative system could simulate complex geometric patterns. Based on the field observation data of trees and knowledge of forestry experts, this paper extracted modeling constraint rules and obtained an L-system rules set. Using the self-developed L-system modeling software the L-system rule set was parsed to generate complex tree 3d models.The results showed that the geometrical modeling method based on l-system could be used to describe the morphological structure of complex trees and generate 3D tree models.

Early competition shapes maize whole-plant development in mixed stands

PubMed Central

Evers, Jochem B.

2014-01-01

Mixed cropping is practised widely in developing countries and is gaining increasing interest for sustainable agriculture in developed countries. Plants in intercrops grow differently from plants in single crops, due to interspecific plant interactions, but adaptive plant morphological responses to competition in mixed stands have not been studied in detail. Here the maize (Zea mays) response to mixed cultivation with wheat (Triticum aestivum) is described. Evidence is provided that early responses of maize to the modified light environment in mixed stands propagate throughout maize development, resulting in different phenotypes compared with pure stands. Photosynthetically active radiation (PAR), red:far-red ratio (R:FR), leaf development, and final organ sizes of maize grown in three cultivation systems were compared: pure maize, an intercrop with a small distance (25cm) between maize and wheat plants, and an intercop with a large distance (44cm) between the maize and the wheat. Compared with maize in pure stands, maize in the mixed stands had lower leaf and collar appearance rates, increased blade and sheath lengths at low ranks and smaller sizes at high ranks, increased blade elongation duration, and decreased R:FR and PAR at the plant base during early development. Effects were strongest in the treatment with a short distance between wheat and maize strips. The data suggest a feedback between leaf initiation and leaf emergence at the plant level and coordination between blade and sheath growth at the phytomer level. A conceptual model, based on coordination rules, is proposed to explain the development of the maize plant in pure and mixed stands. PMID:24307719

An approach to mitigating soil CO2 emission by biochemically inhibiting cellulolytic microbial populations through mediation via the medicinal herb Isatis indigotica

NASA Astrophysics Data System (ADS)

Wu, Hong-Sheng; Chen, Su-Yun; Li, Ji; Liu, Dong-Yang; Zhou, Ji; Xu, Ya; Shang, Xiao-Xia; Wei, Dong-yang; Yu, Lu-ji; Fang, Xiao-hang; Li, Shun-yi; Wang, Ke-ke

2017-06-01

Greenhouse gases (GHGs, particularly carbon dioxide (CO2)) emissions from soil under wheat production are a significant source of agricultural carbon emissions that have not been mitigated effectively. A field experiment and a static incubation study in a lab were conducted to stimulate wheat growth and investigate its potential to reduce CO2 emissions from soil through intercropping with a traditional Chinese medicinal herb called Isatis indigotica. This work was conducted by adding I. indigotica root exudates based on the quantitative real-time PCR (qPCR) analysis of the DNA copy number of the rhizosphere or bulk soil microbial populations. This addition was performed in relation to the CO2 formation by cellulolytic microorganisms (Penicillium oxalicum, fungi and Ruminococcus albus) to elucidate the microbial ecological basis for the molecular mechanism that decreases CO2 emissions from wheat fields using I. indigotica. The results showed that the panicle weight and full grains per panicle measured through intercropping with I. indigotica (NPKWR) increased by 39% and 28.6%, respectively, compared to that of the CK (NPKW). Intercropping with I. indigotica significantly decreased the CO2 emissions from soil under wheat cultivation. Compared with CK, the total CO2 emission flux during the wheat growth period in the I. indigotica (NPKWR) intercropping treatment decreased by 29.26%. The intensity of CO2 emissions per kg of harvested wheat grain declined from 7.53 kg CO2/kg grain in the NPKW (CK) treatment to 5.55 kg CO2/kg grain in the NPKWR treatment. The qPCR analysis showed that the DNA copy number of the microbial populations of cellulolytic microorganisms (P. oxalicum, fungi and R. albus) in the field rhizosphere around I. indigotica or in the bulk soil under laboratory incubation was significantly lower than that of CK. This finding indicated that root exudates from I. indigotica inhibited the activity and number of cellulolytic microbial populations, which led to decreased CO2 emissions, suggesting this plant's potential role in mitigating agricultural GHGs and in supporting agroecology.

Environmental implications of jatropha biofuel from a silvi-pastoral production system in central-west Brazil.

PubMed

Bailis, Rob; Kavlak, Goksin

2013-07-16

We present a life cycle assessment of synthetic paraffinic kerosene produced from Jatropha curcas. The feedstock is grown in an intercropping arrangement with pasture grasses so that Jatropha is coproduced with cattle. Additional innovations are introduced including hybrid seeds, detoxification of jatropha seedcake, and cogeneration. Two fuel pathways are examined including a newly developed catalytic decarboxylation process. Sensitivities are examined including higher planting density at the expense of cattle production as well as 50% lower yields. Intercropping with pasture and detoxifying seedcake yield coproducts that are expected to relieve pressure on Brazil's forests and indirectly reduce environmental impacts of biofuel production. Other innovations also reduce impacts. Results of the baseline assessment indicate that innovations would reduce impacts relative to the fossil fuel reference scenario in most categories including 62-75% reduction in greenhouse gas emissions, 64-82% reduction in release of ozone depleting chemicals, 33-52% reduction in smog-forming pollutants, 6-25% reduction in acidification, and 60-72% reduction in use of nonrenewable energy. System expansion, which explicitly accounts for avoided deforestation, results in larger improvements. Results are robust across allocation methodologies, improve with higher planting density, and persist if yield is reduced by half.

Crop Diversity for Yield Increase

PubMed Central

Li, Chengyun; He, Xiahong; Zhu, Shusheng; Zhou, Huiping; Wang, Yunyue; Li, Yan; Yang, Jing; Fan, Jinxiang; Yang, Jincheng; Wang, Guibin; Long, Yunfu; Xu, Jiayou; Tang, Yongsheng; Zhao, Gaohui; Yang, Jianrong; Liu, Lin; Sun, Yan; Xie, Yong; Wang, Haining; Zhu, Youyong

2009-01-01

Traditional farming practices suggest that cultivation of a mixture of crop species in the same field through temporal and spatial management may be advantageous in boosting yields and preventing disease, but evidence from large-scale field testing is limited. Increasing crop diversity through intercropping addresses the problem of increasing land utilization and crop productivity. In collaboration with farmers and extension personnel, we tested intercropping of tobacco, maize, sugarcane, potato, wheat and broad bean – either by relay cropping or by mixing crop species based on differences in their heights, and practiced these patterns on 15,302 hectares in ten counties in Yunnan Province, China. The results of observation plots within these areas showed that some combinations increased crop yields for the same season between 33.2 and 84.7% and reached a land equivalent ratio (LER) of between 1.31 and 1.84. This approach can be easily applied in developing countries, which is crucial in face of dwindling arable land and increasing food demand. PMID:19956624

Multi-scale measurements show limited soil greenhouse gas emissions in Kenyan smallholder coffee-dairy systems.

PubMed

Ortiz-Gonzalo, Daniel; de Neergaard, Andreas; Vaast, Philippe; Suárez-Villanueva, Víctor; Oelofse, Myles; Rosenstock, Todd S

2018-06-01

Efforts have been made in recent years to improve knowledge about soil greenhouse gas (GHG) fluxes from sub-Saharan Africa. However, data on soil GHG emissions from smallholder coffee-dairy systems have not hitherto been measured experimentally. This study aimed to quantify soil GHG emissions at different spatial and temporal scales in smallholder coffee-dairy farms in Murang'a County, Central Kenya. GHG measurements were carried out for one year, comprising two cropping seasons, using vented static chambers and gas chromatography. Sixty rectangular frames were installed on two farms comprising the three main cropping systems found in the area: 1) coffee (Coffea arabica L.); 2) Napier grass (Pennisetum purpureum); and 3) maize intercropped with beans (Zea mays and Phaseolus vulgaris). Within these fields, chambers were allocated on fertilised and unfertilised locations to capture spatial variability. Cumulative annual fluxes in coffee plots ranged from 1 to 1.9kgN 2 O-Nha -1 , 6.5 to 7.6MgCO 2 -Cha -1 and - 3.4 to -2.2kgCH 4 -Cha -1 , with 66% to 94% of annual GHG fluxes occurring during rainy seasons. Across the farm plots, coffee received most of the N inputs and had 56% to 89% higher emissions of N 2 O than Napier grass, maize and beans. Within farm plots, two to six times higher emissions were found in fertilised hotspots - around the perimeter of coffee trees or within planted maize rows - than in unfertilised locations between trees, rows and planting holes. Background and induced soil N 2 O emissions from fertiliser and manure applications in the three cropping systems were lower than hypothesized from previous studies and empirical models. This study supplements methods and underlying data for the quantification of GHG emissions at multiple spatial and temporal scales in tropical, smallholder farming systems. Advances towards overcoming the dearth of data will facilitate the understanding of synergies and tradeoffs of climate-smart approaches for low emissions development. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Greenhouse gas emissions and stocks of soil carbon and nitrogen from a 20-year fertilised wheat-maize intercropping system: A model approach.

PubMed

Zhang, Xubo; Xu, Minggang; Liu, Jian; Sun, Nan; Wang, Boren; Wu, Lianhai

2016-02-01

Accurate modelling of agricultural management impacts on greenhouse gas emissions and the cycling of carbon and nitrogen is complicated due to interactions between various processes and the disturbance caused by field management. In this study, a process-based model, the Soil-Plant-Atmosphere Continuum System (SPACSYS), was used to simulate the effects of different fertilisation regimes on crop yields, the dynamics of soil organic carbon (SOC) and total nitrogen (SN) stocks from 1990 to 2010, and soil CO2 (2007-2010) and N2O (2007-2008) emissions based on a long-term fertilisation experiment with a winter-wheat (Triticum Aestivum L.) and summer-maize (Zea mays L.) intercropping system in Eutric Cambisol (FAO) soil in southern China. Three fertilisation treatments were 1) unfertilised (Control), 2) chemical nitrogen, phosphorus and potassium (NPK), and 3) NPK plus pig manure (NPKM). Statistical analyses indicated that the SPACSYS model can reasonably simulate the yields of wheat and maize, the evolution of SOC and SN stocks and soil CO2 and N2O emissions. The simulations showed that the NPKM treatment had the highest values of crop yields, SOC and SN stocks, and soil CO2 and N2O emissions were the lowest from the Control treatment. Furthermore, the simulated results showed that manure amendment along with chemical fertiliser applications led to both C (1017 ± 470 kg C ha(-1) yr(-1)) and N gains (91.7 ± 15.1 kg N ha(-1) yr(-1)) in the plant-soil system, while the Control treatment caused a slight loss in C and N. In conclusion, the SPACSYS model can accurately simulate the processes of C and N as affected by various fertilisation treatments in the red soil. Furthermore, application of chemical fertilisers plus manure could be a suitable management for ensuring crop yield and sustaining soil fertility in the red soil region, but the ratio of chemical fertilisers to manure should be optimized to reduce C and N losses to the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Energy budgeting and carbon footprint of transgenic cotton-wheat production system through peanut intercropping and FYM addition.

PubMed

Singh, Raman Jeet; Ahlawat, I P S

2015-05-01

Two of the most pressing sustainability issues are the depletion of fossil energy resources and the emission of atmospheric green house gases like carbon dioxide to the atmosphere. The aim of this study was to assess energy budgeting and carbon footprint in transgenic cotton-wheat cropping system through peanut intercropping with using 25-50% substitution of recommended dose of nitrogen (RDN) of cotton through farmyard manure (FYM) along with 100% RDN through urea and control (0 N). To quantify the residual effects of previous crops and their fertility levels, a succeeding crop of wheat was grown with varying rates of nitrogen, viz. 0, 50, 100, and 150 kg ha(-1). Cotton + peanut-wheat cropping system recorded 21% higher system productivity which ultimately helped to maintain higher net energy return (22%), energy use efficiency (12%), human energy profitability (3%), energy productivity (7%), carbon outputs (20%), carbon efficiency (17%), and 11% lower carbon footprint over sole cotton-wheat cropping system. Peanut addition in cotton-wheat system increased the share of renewable energy inputs from 18 to 21%. With substitution of 25% RDN of cotton through FYM, share of renewable energy resources increased in the range of 21% which resulted into higher system productivity (4%), net energy return (5%), energy ratio (6%), human energy profitability (74%), energy productivity (6%), energy profitability (5%), and 5% lower carbon footprint over no substitution. The highest carbon footprint (0.201) was recorded under control followed by 50 % substitution of RDN through FYM (0.189). With each successive increase in N dose up to 150 kg N ha(-1) to wheat, energy productivity significantly reduced and share of renewable energy inputs decreased from 25 to 13%. Application of 100 kg N ha(-1) to wheat maintained the highest grain yield (3.71 t ha(-1)), net energy return (105,516 MJ ha(-1)), and human energy profitability (223.4) over other N doses applied to wheat. Application of 50 kg N ha(-1) to wheat maintained the least carbon footprint (0.091) followed by 100 kg N ha(-1) (0.100). Our study indicates that system productivity as well as energy and carbon use efficiencies of transgenic cotton-wheat production system can be enhanced by inclusion of peanut as an intercrop in cotton and substitution of 25% RDN of cotton through FYM, as well as application of 100 kg N ha(-1) to succeeding wheat crop.

Towards a Collaborative Research: A Case Study on Linking Science to Farmers’ Perceptions and Knowledge on Arabica Coffee Pests and Diseases and Its Management

PubMed Central

Liebig, Theresa; Läderach, Peter; Poehling, Hans-Michael; Kucel, Patrick; Van Asten, Piet; Avelino, Jacques

2016-01-01

The scientific community has recognized the importance of integrating farmer’s perceptions and knowledge (FPK) for the development of sustainable pest and disease management strategies. However, the knowledge gap between indigenous and scientific knowledge still contributes to misidentification of plant health constraints and poor adoption of management solutions. This is particularly the case in the context of smallholder farming in developing countries. In this paper, we present a case study on coffee production in Uganda, a sector depending mostly on smallholder farming facing a simultaneous and increasing number of socio-ecological pressures. The objectives of this study were (i) to examine and relate FPK on Arabica Coffee Pests and Diseases (CPaD) to altitude and the vegetation structure of the production systems; (ii) to contrast results with perceptions from experts and (iii) to compare results with field observations, in order to identify constraints for improving the information flow between scientists and farmers. Data were acquired by means of interviews and workshops. One hundred and fifty farmer households managing coffee either at sun exposure, under shade trees or inter-cropped with bananas and spread across an altitudinal gradient were selected. Field sampling of the two most important CPaD was conducted on a subset of 34 plots. The study revealed the following findings: (i) Perceptions on CPaD with respect to their distribution across altitudes and perceived impact are partially concordant among farmers, experts and field observations (ii) There are discrepancies among farmers and experts regarding management practices and the development of CPaD issues of the previous years. (iii) Field observations comparing CPaD in different altitudes and production systems indicate ambiguity of the role of shade trees. According to the locality-specific variability in CPaD pressure as well as in FPK, the importance of developing spatially variable and relevant CPaD control practices is proposed. PMID:27504826

Towards a Collaborative Research: A Case Study on Linking Science to Farmers' Perceptions and Knowledge on Arabica Coffee Pests and Diseases and Its Management.

PubMed

Liebig, Theresa; Jassogne, Laurence; Rahn, Eric; Läderach, Peter; Poehling, Hans-Michael; Kucel, Patrick; Van Asten, Piet; Avelino, Jacques

2016-01-01

The scientific community has recognized the importance of integrating farmer's perceptions and knowledge (FPK) for the development of sustainable pest and disease management strategies. However, the knowledge gap between indigenous and scientific knowledge still contributes to misidentification of plant health constraints and poor adoption of management solutions. This is particularly the case in the context of smallholder farming in developing countries. In this paper, we present a case study on coffee production in Uganda, a sector depending mostly on smallholder farming facing a simultaneous and increasing number of socio-ecological pressures. The objectives of this study were (i) to examine and relate FPK on Arabica Coffee Pests and Diseases (CPaD) to altitude and the vegetation structure of the production systems; (ii) to contrast results with perceptions from experts and (iii) to compare results with field observations, in order to identify constraints for improving the information flow between scientists and farmers. Data were acquired by means of interviews and workshops. One hundred and fifty farmer households managing coffee either at sun exposure, under shade trees or inter-cropped with bananas and spread across an altitudinal gradient were selected. Field sampling of the two most important CPaD was conducted on a subset of 34 plots. The study revealed the following findings: (i) Perceptions on CPaD with respect to their distribution across altitudes and perceived impact are partially concordant among farmers, experts and field observations (ii) There are discrepancies among farmers and experts regarding management practices and the development of CPaD issues of the previous years. (iii) Field observations comparing CPaD in different altitudes and production systems indicate ambiguity of the role of shade trees. According to the locality-specific variability in CPaD pressure as well as in FPK, the importance of developing spatially variable and relevant CPaD control practices is proposed.

Nest survival modelling using a multi-species approach in forests managed for timber and biofuel feedstock

USGS Publications Warehouse

Loman, Zachary G.; Monroe, Adrian; Riffell, Samuel K.; Miller, Darren A.; Vilella, Francisco; Wheat, Bradley R.; Rush, Scott A.; Martin, James A.

2018-01-01

Switchgrass (Panicum virgatum) intercropping is a novel forest management practice for biomass production intended to generate cellulosic feedstocks within intensively managed loblolly pine‐dominated landscapes. These pine plantations are important for early‐successional bird species, as short rotation times continually maintain early‐successional habitat. We tested the efficacy of using community models compared to individual surrogate species models in understanding influences on nest survival. We analysed nest data to test for differences in habitat use for 14 bird species in plots managed for switchgrass intercropping and controls within loblolly pine (Pinus taeda) plantations in Mississippi, USA.We adapted hierarchical models using hyper‐parameters to incorporate information from both common and rare species to understand community‐level nest survival. This approach incorporates rare species that are often discarded due to low sample sizes, but can inform community‐level demographic parameter estimates. We illustrate use of this approach in generating both species‐level and community‐wide estimates of daily survival rates for songbird nests. We were able to include rare species with low sample size (minimum n = 5) to inform a hyper‐prior, allowing us to estimate effects of covariates on daily survival at the community level, then compare this with a single‐species approach using surrogate species. Using single‐species models, we were unable to generate estimates below a sample size of 21 nests per species.Community model species‐level survival and parameter estimates were similar to those generated by five single‐species models, with improved precision in community model parameters.Covariates of nest placement indicated that switchgrass at the nest site (<4 m) reduced daily nest survival, although intercropping at the forest stand level increased daily nest survival.Synthesis and applications. Community models represent a viable method for estimating community nest survival rates and effects of covariates while incorporating limited data for rarely detected species. Intercropping switchgrass in loblolly pine plantations slightly increased daily nest survival at the research plot scale (0.1 km2), although at a local scale (50 m2) switchgrass negatively influenced nest survival. A likely explanation is intercropping shifted community composition, favouring species with greater disturbance tolerance.

Object-oriented fault tree models applied to system diagnosis

NASA Technical Reports Server (NTRS)

Iverson, David L.; Patterson-Hine, F. A.

1990-01-01

When a diagnosis system is used in a dynamic environment, such as the distributed computer system planned for use on Space Station Freedom, it must execute quickly and its knowledge base must be easily updated. Representing system knowledge as object-oriented augmented fault trees provides both features. The diagnosis system described here is based on the failure cause identification process of the diagnostic system described by Narayanan and Viswanadham. Their system has been enhanced in this implementation by replacing the knowledge base of if-then rules with an object-oriented fault tree representation. This allows the system to perform its task much faster and facilitates dynamic updating of the knowledge base in a changing diagnosis environment. Accessing the information contained in the objects is more efficient than performing a lookup operation on an indexed rule base. Additionally, the object-oriented fault trees can be easily updated to represent current system status. This paper describes the fault tree representation, the diagnosis algorithm extensions, and an example application of this system. Comparisons are made between the object-oriented fault tree knowledge structure solution and one implementation of a rule-based solution. Plans for future work on this system are also discussed.

[Effects of legume-oat intercropping on abundance and community structure of soil N2-fixing bacteria].

PubMed

Yang, Ya Dong; Feng, Xiao Min; Hu, Yue Gao; Ren, Chang Zhong; Zeng, Zhao Hai

2017-03-18

In this study, real-time PCR and high-throughput sequencing approaches were employed to investigate the abundance and community structure of N 2 -fixing bacteria in a field experiment with three planting patterns (Oat monoculture, O; Soybean-oat intercropping, OSO; Mung bean-oat intercropping, OMO). The results showed that soil chemical properties varied significantly in different soil samples (P＜0.05). The abundance of nifH gene varied from 1.75×10 10 to 7.37×10 10 copies·g -1 dry soil in all soil samples. The copy numbers of nifH gene in OSO and OMO were 2.18, 2.64, and 1.92, 2.57 times as much as that in O at jointing and mature stages, with a significant decline from jointing to mature stage for all treatments (P＜0.05). Rarefaction curve and cove-rage results proved the nifH gene sequencing results were reliable, and the diversity index showed that the N 2 -fixing bacteria diversity of OSO was much higher than that of O. Azohydromonas, Azotobacter, Bradyrhizobium, Skermanella and other groups that could not be classified are the dominant genera, with significant differences in proportion of these dominant groups observed among all soil samples (P＜0.05). Venn and PCA analysis indicated that there were greater differences of nifH gene communities between jointing and mature stages; however, the OSO and OMO had similar communities in both stages. All these results confirmed that legume-oat intercropping significantly increased the abundance and changed the community composition of N 2 -fixing bacteria in oat soils.

Intercrop movement of convergent lady beetle, Hippodamia convergens (Coleoptera: Coccinellidae), between adjacent cotton and alfalfa.

PubMed

Bastola, Anup; Parajulee, Megha N; Porter, R Patrick; Shrestha, Ram B; Chen, Fa-Jun; Carroll, Stanley C

2016-02-01

A 2-year study was conducted to characterize the intercrop movement of convergent lady beetle, Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae) between adjacent cotton and alfalfa. A dual protein-marking method was used to assess the intercrop movement of the lady beetles in each crop. In turns field collected lady beetles in each crop were assayed by protein specific ELISA to quantify the movement of beetles between the crops. Results indicated that a high percentage of convergent lady beetles caught in cotton (46% in 2008; 56% in 2009) and alfalfa (46% in 2008; 71% in 2009) contained a protein mark, thus indicating that convergent lady beetle movement was largely bidirectional between the adjacent crops. Although at a much lower proportion, lady beetles also showed unidirectional movement from cotton to alfalfa (5% in 2008 and 6% in 2009) and from alfalfa to cotton (9% in 2008 and 14% in 2009). The season-long bidirectional movement exhibited by the beetles was significantly higher in alfalfa than cotton during both years of the study. The total influx of lady beetles (bidirectional and unidirectional combined) was significantly higher in alfalfa compared with that in cotton for both years. While convergent lady beetles moved between adjacent cotton and alfalfa, they were more attracted to alfalfa when cotton was not flowering and/or when alfalfa offered more opportunities for prey. This study offers much needed information on intercrop movement of the convergent lady beetle that should facilitate integrated pest management decisions in cotton utilizing conservation biological control. © 2014 Institute of Zoology, Chinese Academy of Sciences.

[Effect of Astragalus membranaceus var. mongholicus seed extracts on seed germination and seedling growth of different Codonopsis pilosula caltiver].

PubMed

Guo, Feng-Xia; Wu, Zhi-Jiang; Chen, Yuan; Xi, Zhuo-Xia; Zhang, Xiao-Hu; Yao, Li-Rong; Chen, Xiang

2012-11-01

To reveal the allelopathy effect of Astragalus membranaceus var. mongholicus seeds and provide information for the intercrop production. The A. membranaceus. var. mongholicus seeds were soaked in distilled water for different time (12, 24, 36, 48, 60 h) , and then the seed extracts were used to study their effects on the seed germination, seedling growth and development of two Codonopsis pilosula. The A. membranaceus var. mongholicus seeds contained some allelopathy compounds. Their soaked liquid had significantly influence on the seed germination and seedling growth of C. pilosula. The seed germination rate, germination power, germination index and vigor index of two C. pilosula calrivar were improved and then inhabited with soaking time elongation. The extract soaking for 24 h significantly improved the germination traits but the extract for 60 h appeared different degrees of inhibiting vigor. The seed extracts soaking ranging between 12 and 60 h all significantly improved the above plant growth of C. pilosula but significant inhibited their radicle growth in length. And with the soaking time elongation the facilitation effect weakened and the inhibiting effect enhanced, especially more significant in the C. pilosula caltivar (Baitiaodangshen). The A. membranaceus var. mongholicus seeds have allelopathic compounds and the endogenous inhibitor can be extracted when soaked for more than 24 h in water with intact seeds, resulting in improvement of seed germination rate. The C. pilosula could be intercropped in A. membranaceus var. mongholicus field, however, when intercroped it should notice that the intercrop proportion should vary with the caltivar.

No correlation between the diversity and productivity of assemblages: evidence from the phytophage and predator assemblages in various cotton agroecosystems.

PubMed

Gao, Feng; Men, XingYuan; Ge, Feng

2014-09-01

Biodiversity research has shown that primary productivity increases with plant species number, especially in many experimental grassland systems. Here, we assessed the correlation between productivity and diversity of phytophages and natural enemy assemblages associated with planting date and intercropping in four cotton agroecosystems. Twenty-one pairs of data were used to determine Pearson correlations between species richness, total number of individuals, diversity indices and productivity for each assemblage every five days from 5 June to 15 September 2012. At the same trophic level, the productivity exhibited a significant positive correlation with species richness of the phytophage or predator assemblage. A significant correlation was found between productivity and total number of individuals in most cotton fields. However, no significant correlations were observed between productivity and diversity indices (including indices of energy flow diversity and numerical diversity) in most cotton fields for either the phytophage or the predator assemblages. Species richness of phytophage assemblage and total individual numbers were significantly correlated with primary productivity. Also, species richness of natural enemy assemblage and total number of individuals correlated with phytophage assemblage productivity. A negative but not significant correlation occurred between the indices of numerical diversity and energy flow diversity and lower trophic-level productivity in the cotton-phytophage and phytophage-predator assemblages for most intercropped cotton agroecosystems. Our results clearly showed that there were no correlations between diversity indices and productivity within the same or lower trophic levels within the phytophage and predator assemblages in cotton agroecosystems, and inter-cropped cotton fields had a stronger ability to support the natural enemy assemblage and potentially to reduce phytophages.

Biochar and Glomus caledonium Influence Cd Accumulation of Upland Kangkong (Ipomoea aquatica Forsk.) Intercropped with Alfred Stonecrop (Sedum alfredii Hance)

NASA Astrophysics Data System (ADS)

Hu, Junli; Wu, Fuyong; Wu, Shengchun; Lam, Cheung Lung; Lin, Xiangui; Wong, Ming Hung

2014-04-01

Both biochar application and mycorrhizal inoculation have been proposed to improve plant growth and alter bioaccumulation of toxic metals. A greenhouse pot trial was conducted to investigate growth and Cd accumulation of upland kangkong (Ipomoea aquatica Forsk.) intercropped with Alfred stonecrop (Sedum alfredii Hance) in a Cd-contaminated soil inoculated with Glomus caledonium and/or applied with biochar. Compared with the monocultural control, intercropping with stonecrop (IS) decreased kangkong Cd acquisition via rhizosphere competition, and also decreased kangkong yield. Gc inoculation (+M) accelerated growth and Cd acquisition of stonecrop, and hence resulted in further decreases in kangkong Cd acquisition. Regardless of IS and +M, biochar addition (+B) increased kangkong yield via elevating soil available P, and decreased soil Cd phytoavailability and kangkong Cd concentration via increasing soil pH. Compared with the control, the treatment of IS + M + B had a substantially higher kangkong yield (+25.5%) with a lower Cd concentration (-62.7%). Gc generated additive effects on soil alkalinization and Cd stabilization to biochar, causing lower DTPA-extractable (phytoavailable) Cd concentrations and post-harvest transfer risks.

A High-Throughput Molecular Pipeline Reveals the Diversity in Prevalence and Abundance of Pratylenchus and Meloidogyne Species in Coffee Plantations.

PubMed

Bell, Christopher A; Atkinson, Howard J; Andrade, Alan C; Nguyen, Hoa X; Swibawa, I Gede; Lilley, Catherine J; McCarthy, James; Urwin, P E

2018-05-01

Coffee yields are adversely affected by plant-parasitic nematodes and the pathogens are largely underreported because a simple and reliable identification method is not available. We describe a polymerase chain reaction-based approach to rapidly detect and quantify the major Pratylenchus and Meloidogyne nematode species that are capable of parasitizing coffee. The procedure was applied to soil samples obtained from a number of coffee farms in Brazil, Vietnam, and Indonesia to assess the prevalence of these species associated both with coffee (Coffea arabica and C. canephora) and its intercropped species Musa acuminata (banana) and Piper nigrum (black pepper). Pratylenchus coffeae and P. brachyurus were associated with coffee in all three countries but there were distinct profiles of Meloidogyne spp. Meloidogyne incognita, M. exigua, and M. paranaensis were identified in samples from Brazil and M. incognita and M. hapla were detected around the roots of coffee in Vietnam. No Meloidogyne spp. were detected in samples from Indonesia. There was a high abundance of Meloidogyne spp. in soil samples in which Pratylenchus spp. were low or not detected, suggesting that the success of one genus may deter another. Meloidogyne spp. in Vietnam and Pratylenchus spp. in Indonesia were more numerous around intercropped plants than in association with coffee. The data suggest a widespread but differential nematode problem associated with coffee production across the regions studied. The issue is compounded by the current choice of intercrops that support large nematode populations. Wider application of the approach would elucidate the true global scale of the nematode problem and the cost to coffee production. [Formula: see text] Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

[Studies on the shade-endurance capacity of Glycyrrhiza uralensis].

PubMed

Wei, Sheng-li; Wang, Wen-quan; Chen, Xiu-hua; Qin, Shu-ying; Chen, Xiu-tian

2005-01-01

To study the shade-endurance property of Glycyrrhiza uralensis and provide rationale for the practice of inter-cropping G. uralensis with trees. Black shading nets were used to provide five different environments of light intensities (light penetration rates of 100%, 75%, 65%, 50% and 25%, respectively). To assess the shade-endurance capacity of G. uralensis, several aspects were evaluated, including growth characters, physiological and ecological characters, biomass, and chemical contents. G. uralensis is a light-favored plant. The growth indices such as plant height, stem diameter, leaves number, root diameter, biomass, and daily average photosynthetic rate (Pn) are highest when light permeation rate is 100%. All these indices decrease when light intensity decreases. However, G. uralensis possesses shade-endurance capacity to some degree; it adapts to the shading environment by increasing the leaf area and chlorophyll contents. Shading has no obvious effect on the absolute light energy utilization rate (Eu) or Fv/Fm ratio. The influence of shading on the chemical contents of G. uralensis is obvious.

Faults Discovery By Using Mined Data

NASA Technical Reports Server (NTRS)

Lee, Charles

2005-01-01

Fault discovery in the complex systems consist of model based reasoning, fault tree analysis, rule based inference methods, and other approaches. Model based reasoning builds models for the systems either by mathematic formulations or by experiment model. Fault Tree Analysis shows the possible causes of a system malfunction by enumerating the suspect components and their respective failure modes that may have induced the problem. The rule based inference build the model based on the expert knowledge. Those models and methods have one thing in common; they have presumed some prior-conditions. Complex systems often use fault trees to analyze the faults. Fault diagnosis, when error occurs, is performed by engineers and analysts performing extensive examination of all data gathered during the mission. International Space Station (ISS) control center operates on the data feedback from the system and decisions are made based on threshold values by using fault trees. Since those decision-making tasks are safety critical and must be done promptly, the engineers who manually analyze the data are facing time challenge. To automate this process, this paper present an approach that uses decision trees to discover fault from data in real-time and capture the contents of fault trees as the initial state of the trees.

Intercropping with white lupin (Lupinus albus L.); a promising tool for phytoremediation and phytomining research

NASA Astrophysics Data System (ADS)

Wiche, Oliver; Székely, Balazs; Moschner, Christin; Heilmeier, Hermann

2015-04-01

In recent studies root-soil interactions of white lupine (Lupinus albus L.) have drawn special attention to researchers due to its particularly high potential to increase bioavailability of phosphorous (P) and trace nutrients in soils. In mixed cultures, white lupine has the ability to mobilize P and trace nutrients in soil in excess of its own need and make this excess available for other intercropped companion species. While improved acquisition of P and improved yield parameters have mostly been documented in cereal-lupine intercrops, compared to sole crops, only a few recent studies have evidenced similar effects for trace elements e.g. Fe, Zn and Mn. In this preliminary study we tried to obtain more information about the mobilization of trace elements due to intercropping under field conditions. We hypothesize, that processes that lead to a better acquisition of trace nutrients might also affect other trace elements what could be useful for phytoremediation and phytomining research. Here we report the results of a semi-field experiment were we investigated the effects of an intercropping of white lupine with oat (Avena sativa L.) on the concentrations of trace metals in shoots of oat. We investigated the effects on 12 trace elements, including 4 elements with relevance for plant nutrition (P, Fe, Mn, Zn) and 8 trace elements, belonging to the group of metalloids, lanthanides and actinides with high relevance in phytoremediation (Cd, Pb Th, U) and phytomining research (Sc, La, Nd, Ge). The experiment was carried out on a semi-field lysimer at the off-site soil recycling and remediation center in Hirschfeld (Saxony, Germany). To test the intercropping-dependent mobilization of trace metals in soil and enhanced uptake of elements by oat, white lupine and oat were cultivated on 20 plots (4 m² each) in monocultures and mixed cultures and two different white lupin /oat-ratios (11% and 33%, respectively) applying various treatments. The geometrical arrangement of plots was randomized and every treatment was fivefold replicated. Soil solution was collected weekly with plastic suction cups. Concentrations of trace metals in shoots of oat and soil solution were measured with ICP-MS. As a result, we found that both, concentrations of trace elements in oat plants, as well as the mobility of P and trace metals in soil solution was increased by an intercropping with white lupine. Mixed culture of oat with 11% white lupin significantly increased the concentrations of the trace nutrients Fe, Mn and Zn, as well as the concentrations of the trace metals Pb, La, Nd, Sc, Th and U in tissues of oat. Surprisingly, mixed cultures with 33 % white lupin did not significantly affect trace metal concentrations in oat, what might be the consequence of an increasing competition of roots of white lupin and oat for nutrients and trace metals. In conclusion we found that mixed cultures of white lupin with cereals might be a powerful tool for enhanced phytoremediation and phytomining. However, processes involved in the physiochemical mechanism of element uptake as affected by the oat/white lupin co-cultivation remain unknown and further studies on this topic are planned. These studies have been carried out in the framework of the PhytoGerm project, financed by the Federal Ministry of Education and Research, Germany. The authors are grateful to students and laboratory assistants contributing in the field work and sample preparation.

Effects of applying molasses, lactic acid bacteria and propionic acid on fermentation quality, aerobic stability and in vitro gas production of total mixed ration silage prepared with oat-common vetch intercrop on the Tibetan Plateau.

PubMed

Chen, Lei; Guo, Gang; Yuan, Xianjun; Zhang, Jie; Li, Junfeng; Shao, Tao

2016-03-30

The objective of this study was to investigate the effect of molasses, lactic acid bacteria and propionic acid on the fermentation quality, aerobic stability and in vitro gas production of total mixed ration (TMR) silage prepared with oat-common vetch intercrop on the Tibetan plateau. TMR (436 g kg(-1) dry matter (DM)) was ensiled with six experimental treatments: (1) no additives (control); (2) molasses (M); (3) an inoculant (Lactobacillus plantarum) (L); (4) propionic acid (P); (5) molasses + propionic acid (MP); (6) inoculant + propionic acid (LP). All silages were well preserved with low pH (< 4.19) and NH3-N contents, and high lactic acid contents after ensiling for 45 days. L and PL silages underwent a more efficient fermentation than silages without L. P and MP silages inhibited lactic acid production. Under aerobic conditions, M and L silage reduced aerobic stability for 15 and 74 h, respectively. All silages that had propionic acid in their treatments markedly (P < 0.05) improved the aerobic stability. After 72 h incubation, all additives treatments increased (P < 0.05) the 72 h cumulative gas production and in vitro DM digestibility (IVDMD) as compared with the control. L treatment decreased (P < 0.05) in vitro neutral detergent fibre degradability. Our findings show that TMR prepared with oat-common vetch intercrop can be well preserved. Although propionic acid is compatible with lactic acid bacteria, and when used together, they had minor effects on fermentation, aerobic stability and in vitro digestibility of TMR silage prepared with oat-common vetch intercrop. © 2015 Society of Chemical Industry.

Evaluation of ecofriendly management practices of french beanrust (Uromyces appendiculatus) in organic farming system

NASA Astrophysics Data System (ADS)

Chhetry, G. K. N.; Mangang, H. C.

2012-09-01

Organic farming system emphasises on sustainable development of agriculture. The traditional agriculture system was much akin to the organic system but modernization of agriculture made a shift to this trend. The north east region of India is potential organic farming sites. Most of the farming systems are traditional and are organic by default; however crops in organic farming are prone to many fungal diseases. Hence for validation of the impact of organic practices on the disease development of plants, a study has been conducted for three years under natural environmental conditions on bean rust (Uromyces appendiculatus). Study includes ecofriendly practices like: plant extract treatment, intercropping of beans with maize, organic manure application, influence of cropping season and Trichoderma treatment. Rust is a major prevalent disease in the cultivation of beans as in other parts of the world. Detailed study of the disease in the organic environment and the impact of various treatments and agricultural agronomic practices would help in validation of the practices for the management of the disease in the organic farming system. In our study for three consecutive years it has been revealed that the practices of the traditional farmers likeplant extract application, intercropping, and manure application were found to have significant positive effects in reducing rust development in the bean fields. The treatment of farm yard manure resulted in development of lesser area under disease progress curve. The plant extract of Artemisia vulgaris has marked positive impact on reducing rust disease parameters. Foliar application of Trichoderma reduces the disease parameters of rust. This study would enhance information in understanding the impact of organic farming system on bean rust and would help in validitation of sustainable agricultural practices for use in organic farming system.

Biochar and Glomus caledonium Influence Cd Accumulation of Upland Kangkong (Ipomoea aquatica Forsk.) Intercropped with Alfred Stonecrop (Sedum alfredii Hance)

PubMed Central

Hu, Junli; Wu, Fuyong; Wu, Shengchun; Lam, Cheung Lung; Lin, Xiangui; Wong, Ming Hung

2014-01-01

Both biochar application and mycorrhizal inoculation have been proposed to improve plant growth and alter bioaccumulation of toxic metals. A greenhouse pot trial was conducted to investigate growth and Cd accumulation of upland kangkong (Ipomoea aquatica Forsk.) intercropped with Alfred stonecrop (Sedum alfredii Hance) in a Cd-contaminated soil inoculated with Glomus caledonium and/or applied with biochar. Compared with the monocultural control, intercropping with stonecrop (IS) decreased kangkong Cd acquisition via rhizosphere competition, and also decreased kangkong yield. Gc inoculation (+M) accelerated growth and Cd acquisition of stonecrop, and hence resulted in further decreases in kangkong Cd acquisition. Regardless of IS and +M, biochar addition (+B) increased kangkong yield via elevating soil available P, and decreased soil Cd phytoavailability and kangkong Cd concentration via increasing soil pH. Compared with the control, the treatment of IS + M + B had a substantially higher kangkong yield (+25.5%) with a lower Cd concentration (−62.7%). Gc generated additive effects on soil alkalinization and Cd stabilization to biochar, causing lower DTPA-extractable (phytoavailable) Cd concentrations and post-harvest transfer risks. PMID:24728157

Diagnosis of nutrient imbalances with vector analysis in agroforestry systems.

PubMed

Isaac, Marney E; Kimaro, Anthony A

2011-01-01

Agricultural intensification has had unintended environmental consequences, including increased nutrient leaching and surface runoff and other agrarian-derived pollutants. Improved diagnosis of on-farm nutrient dynamics will have the advantage of increasing yields and will diminish financial and environmental costs. To achieve this, a management support system that allows for site-specific rapid evaluation of nutrient production imbalances and subsequent management prescriptions is needed for agroecological design. Vector diagnosis, a bivariate model to depict changes in yield and nutritional response simultaneously in a single graph, facilitates identification of nutritional status such as growth dilution, deficiency, sufficiency, luxury uptake, and toxicity. Quantitative data from cocoa agroforestry systems and pigeonpea intercropping trials in Ghana and Tanzania, respectively, were re-evaluated with vector analysis. Relative to monoculture, biomass increase in cocoa ( L.) under shade (35-80%) was accompanied by a 17 to 25% decline in P concentration, the most limiting nutrient on this site. Similarly, increasing biomass with declining P concentrations was noted for pigeonpea [ (L). Millsp.] in response to soil moisture availability under intercropping. Although vector analysis depicted nutrient responses, the current vector model does not consider non-nutrient resource effects on growth, such as ameliorated light and soil moisture, which were particularly active in these systems. We revisit and develop vector analysis into a framework for diagnosing nutrient and non-nutrient interactions in agroforestry systems. Such a diagnostic technique advances management decision-making by increasing nutrient precision and reducing environmental issues associated with agrarian-derived soil contamination. American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

Plant disease management in organic farming systems.

PubMed

van Bruggen, Ariena H C; Gamliel, Abraham; Finckh, Maria R

2016-01-01

Organic farming (OF) has significantly increased in importance in recent decades. Disease management in OF is largely based on the maintenance of biological diversity and soil health by balanced crop rotations, including nitrogen-fixing and cover crops, intercrops, additions of manure and compost and reductions in soil tillage. Most soil-borne diseases are naturally suppressed, while foliar diseases can sometimes be problematic. Only when a severe disease outbreak is expected are pesticides used that are approved for OF. A detailed overview is given of cultural and biological control measures. Attention is also given to regulated pesticides. We conclude that a systems approach to disease management is required, and that interdisciplinary research is needed to solve lingering disease problems, especially for OF in the tropics. Some of the organic regulations are in need of revision in close collaboration with various stakeholders. © 2015 Society of Chemical Industry.

Software For Fault-Tree Diagnosis Of A System

NASA Technical Reports Server (NTRS)

Iverson, Dave; Patterson-Hine, Ann; Liao, Jack

1993-01-01

Fault Tree Diagnosis System (FTDS) computer program is automated-diagnostic-system program identifying likely causes of specified failure on basis of information represented in system-reliability mathematical models known as fault trees. Is modified implementation of failure-cause-identification phase of Narayanan's and Viswanadham's methodology for acquisition of knowledge and reasoning in analyzing failures of systems. Knowledge base of if/then rules replaced with object-oriented fault-tree representation. Enhancement yields more-efficient identification of causes of failures and enables dynamic updating of knowledge base. Written in C language, C++, and Common LISP.

A new tree classification system for southern hardwoods

Treesearch

James S. Meadows; Daniel A. Jr. Skojac

2008-01-01

A new tree classification system for southern hardwoods is described. The new system is based on the Putnam tree classification system, originally developed by Putnam et al., 1960, Management ond inventory of southern hardwoods, Agriculture Handbook 181, US For. Sew., Washington, DC, which consists of four tree classes: (1) preferred growing stock, (2) reserve growing...

Spider assemblages associated with different crop stages of irrigated rice agroecosystems from eastern Uruguay

PubMed Central

Ginella, Juaquín; Cadenazzi, Mónica; Castiglioni, Enrique A.; Martínez, Sebastián; Casales, Luis; Caraballo, María P.; Laborda, Álvaro; Simo, Miguel

2018-01-01

Abstract The rice crop and associated ecosystems constitute a rich mosaic of habitats that preserve a rich biological diversity. Spiders are an abundant and successful group of natural predators that are considered efficient in the biocontrol of the major insect pests in agroecosystems. Spider diversity in different stages of the rice crop growth from eastern Uruguay was analysed. Field study was developed on six rice farms with rotation system with pasture, installed during intercropping stage as cover crop. Six rice crops distributed in three locations were sampled with pitfall and entomological vaccum suction machine. Sixteen families, representing six guilds, were collected. Lycosidae, Linyphiidae, Anyphaenidae and Tetragnathidae were the most abundant families (26%, 25%, 20% and 12%, respectively) and comprised more than 80% of total abundance. Other hunters (29%), sheet web weavers (25%) and ground hunters (24%) were the most abundant guilds. Species composition along different crop stages was significantly different according to the ANOSIM test. The results showed higher spider abundance and diversity along the crop and intercrop stages. This study represents the first contribution to the knowledge of spider diversity associated with rice agroecosystem in the country. PMID:29755261

Impacts of transgenic poplar-cotton agro-ecosystems upon target pests and non-target insects under field conditions.

PubMed

Zhang, D J; Liu, J X; Lu, Z Y; Li, C L; Comada, E; Yang, M S

2015-07-27

Poplar-cotton agro-ecosystems are the main agricultural planting modes of cotton fields in China. With increasing acres devoted to transgenic insect-resistant poplar and transgenic insect-resistant cotton, studies examining the effects of transgenic plants on target and non-target insects become increasingly important. We systematically surveyed populations of both target pests and non-target insects for 4 different combinations of poplar-cotton eco-systems over 3 years. Transgenic Bt cotton strongly resisted the target insects Fall webworm moth [Hyphantria cunea (Drury)], Sylepta derogata Fabrieius, and American bollworm (Heliothis armigera), but no clear impact on non-target insect cotton aphids (Aphis gossypii). Importantly, intercrops containing transgenic Pb29 poplar significantly increased the inhibitory effects of Bt cotton on Fall webworm moth in ecosystem IV. Highly resistant Pb29 poplar reduced populations of the target pests Grnsonoma minutara Hubner and non-target insect poplar leaf aphid (Chaitophorus po-pulialbae), while Fall webworm moth populations were unaffected. We determined the effects of Bt toxin from transgenic poplar and cotton on target and non-target pests in different ecosystems of cotton-poplar intercrops and identified the synergistic effects of such combinations toward both target and non-target insects.

Spider assemblages associated with different crop stages of irrigated rice agroecosystems from eastern Uruguay.

PubMed

Bao, Leticia; Ginella, Juaquín; Cadenazzi, Mónica; Castiglioni, Enrique A; Martínez, Sebastián; Casales, Luis; Caraballo, María P; Laborda, Álvaro; Simo, Miguel

2018-01-01

The rice crop and associated ecosystems constitute a rich mosaic of habitats that preserve a rich biological diversity. Spiders are an abundant and successful group of natural predators that are considered efficient in the biocontrol of the major insect pests in agroecosystems. Spider diversity in different stages of the rice crop growth from eastern Uruguay was analysed. Field study was developed on six rice farms with rotation system with pasture, installed during intercropping stage as cover crop. Six rice crops distributed in three locations were sampled with pitfall and entomological vaccum suction machine. Sixteen families, representing six guilds, were collected. Lycosidae, Linyphiidae, Anyphaenidae and Tetragnathidae were the most abundant families (26%, 25%, 20% and 12%, respectively) and comprised more than 80% of total abundance. Other hunters (29%), sheet web weavers (25%) and ground hunters (24%) were the most abundant guilds. Species composition along different crop stages was significantly different according to the ANOSIM test. The results showed higher spider abundance and diversity along the crop and intercrop stages. This study represents the first contribution to the knowledge of spider diversity associated with rice agroecosystem in the country.

Lighting a dark corner.

PubMed

Choto, R

1998-01-01

In Karanga community, 410 km south of Harare, Zimbabwe, the Intermediate Technology Development Group's (ITDG) farming project has successfully improved household food security through its farming project. The ITDG encouraged the formation of 35 women's garden clubs that have allowed women to reduce their individual labor, become closer to each other, and incorporate improved farming methods to increase crop production. The ITDG started work in 1991, just before a severe drought in 1992 forced over 770,000 people to rely on aid for food. ITDG changed the unsuccessful, top-down approach of state agricultural workers to a more successful, bottom-up approach. It also reintroduced intercropping and integrated farming systems to compensate for the fact that the average number of households of six people manages with only about a hectare of land. Indigenous methods, such as intercropping onions for pest management, are reducing reliance on chemicals, and chicken and goal manure is used for fertilizer. In addition to improving food security and nutrition, the gardens are producing enough surplus vegetables for sale. ITDG has also assisted the drought-prone community in developing water conservation techniques that use infiltration pits and gravity to nourish the soil after the rains have stopped.

Energetics and environmental costs of agriculture in a dry tropical region of India

NASA Astrophysics Data System (ADS)

Singh, V. P.; Singh, J. S.

1992-07-01

The present article, based on a study of five village ecosystems, assesses the energy efficiency of rain-fed agriculture in a dry tropical environment and the impact of agricultural activity on the surrounding natural ecosystems. Agronomic yield is insufficient to meet the food requirement of the human population, hence 11.5%-49.7% of the required amount of food grains are imported from the market. Energy requirements of five studied agroecosystems are subsidized considerably by the surrounding forest in the form of fodder and firewood. Natural ecosystems supply about 80%-95% of fodder needs and 81%-100% of fuelwood needs. The output-input ratio of agriculture indicated that, on average, 4.1 units of energy are expended to obtain one unit of agronomic energy. Of this, 3.9 units are supplied by the natural ecosystem. In addition, 38% of the extracted firewood is marketed. The illegal felling and lopping of trees result in ever-increasing concentric circles of forest destruction around the villages and together with excessive grazing results in savannization. The forests can be conserved by encouraging fuelwood plantations (0.7 ha/ha cultivated land) and developing village pastures (1.6 ha/ha cultivated land) and reducing the livestock numbers. Agricultural production in the region can be stabilized by introducing improved dry farming techniques such as intercropping, planned rainwater management, and adequate use of fertilizers.

A generalized system of models forecasting Central States tree growth.

Treesearch

Stephen R. Shifley

1987-01-01

Describes the development and testing of a system of individual tree-based growth projection models applicable to species in Indiana, Missouri, and Ohio. Annual tree basal area growth is estimated as a function of tree size, crown ratio, stand density, and site index. Models are compatible with the STEMS and TWIGS Projection System.

The weakest t-norm based intuitionistic fuzzy fault-tree analysis to evaluate system reliability.

PubMed

Kumar, Mohit; Yadav, Shiv Prasad

2012-07-01

In this paper, a new approach of intuitionistic fuzzy fault-tree analysis is proposed to evaluate system reliability and to find the most critical system component that affects the system reliability. Here weakest t-norm based intuitionistic fuzzy fault tree analysis is presented to calculate fault interval of system components from integrating expert's knowledge and experience in terms of providing the possibility of failure of bottom events. It applies fault-tree analysis, α-cut of intuitionistic fuzzy set and T(ω) (the weakest t-norm) based arithmetic operations on triangular intuitionistic fuzzy sets to obtain fault interval and reliability interval of the system. This paper also modifies Tanaka et al.'s fuzzy fault-tree definition. In numerical verification, a malfunction of weapon system "automatic gun" is presented as a numerical example. The result of the proposed method is compared with the listing approaches of reliability analysis methods. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

The land use patterns for soil organic carbon conservation at Endanga watershed Southeast Sulawesi Indonesia

NASA Astrophysics Data System (ADS)

Leomo, S.; Ginting, S.; Sabaruddin, L.; Tufaila, M.; Muhidin

2018-02-01

The Endanga basin is one part of the Konaweeha watershed located in South Konawe, Southeast Sulawesi Province, covering an area of 1,353.67 hectares. The land use patterns in Endanga Watershed contained forests, shrubs, oil palm plantations, pepper fields, and cultivated fields of field rice, corn monoculture and intercropping of peanuts and corn. This watershed needs serious attention because most of its territory is on slope of 15-40%, with erosion hazard levels (EHL) varying from mild erosion to severe erosion. The loss of organic carbon (C-organic) soil is measured from the soil carried along with the surface stream and into the reservoir on various land uses. The result measurement of C-organic soil loss on forest land use is 14.02 kg ha-1, shrubs land 22.71 kg ha-1, oil palm 151.32 kg ha-1, pepper garden 93.69 kg ha-1, field rice 313.80 kg.ha-1, monoculture of maize 142.44 kg ha-1, intercropped maize and corn 51.10 kg ha-1 and open land 1,909.16 kg ha-1. The forest land and shrubs is best in conserving soil C-organic, but economically unfavorable for the community, so land use pattern for intercropping and pepper plantation can be used for soil C-organic conservation

Uptake of di(2-ethylhexyl) phthalate (DEHP) by the plant Benincasa hispida and its use for lowering DEHP content of intercropped vegetables.

PubMed

Wu, Zunyi; Zhang, Xiaolei; Wu, Xiaolian; Shen, Guoming; Du, Qizhen; Mo, Cehui

2013-06-05

Uptake of di(2-ethylhexyl) phthalate (DEHP) by the plant Benincasa hispida and its use for topical phytoremediation were investigated by cultivation of plants in DEHP-contaminated environments. The results showed that major plant organs of B. hispida , including leaves, stems, and fruits, readily absorbed DEHP from the air. The amount of DEHP that accumulated in leaves, stems, and fruits was mainly dependent upon exposure time, and most DEHP accumulated in their inner tissues. A single plant of B. hispida with a gourd was able to absorb more than 700 mg of DEHP when it was exposed to DEHP-contaminated air for 6 week. B. hispida reduced air DEHP concentration by 65-76% as the air DEHP concentration ranged from 2351 to 3955 μg/m³ (high DEHP level) and 85-92% as the air DEHP concentration ranged from 35.1 to 65.3 μg/m³ (low DEHP level) in greenhouse experiments. When intercropping of B. hispida and Brassica chinensis or Brassica campestris , B. hispida reduced more than 87% of DEHP accumulation in the latter, which indicates that B. hispida has excellent use potential for lowering the DEHP content of intercropped vegetables.

Soil Modification by Native Shrubs Boosts Crop Productivity in Sudano-Sahelian Agroforestry System

NASA Astrophysics Data System (ADS)

Bogie, N. A.; Bayala, R.; Diedhiou, I.; Ghezzehei, T. A.; Dick, R.

2014-12-01

A changing climate along with human and animal population pressure can have a devastating effect on crop yields and food security in the Sudano-Sahel. Agricultural solutions to address soil degradation and crop water stress are needed to combat this increasingly difficult situation. Significant differences in crop success have been observed in peanut and millet grown in association with two native evergreen shrubs Piliostigma reticulatum, and Guiera senegalensis at the sites of Nioro du Rip and Keur Matar, respectively.We investigate how farmers can increase crop productivity by capitalizing on the evolutionary adaptation of native shrubs to the harsh Sudano-Sahelian environment as well as the physical mechanisms at work in the system that can lead to more robust yields. Soil moisture and water potential data were collected during a dry season millet irrigation experiment where stress was imposed in the intercropped system. Despite lower soil moisture content, crops grown in association with shrubs have increased biomass production and a faster development cycle. Hydraulic redistribution is thought to exist in this system and we found diurnal fluctuations in water potential within the intercropped system that increased in magnitude of to 0.4 Mpa per day as the soil dried below 1.0 Mpa during the stress treatment. An isotopic tracer study investigating hydraulic redistribution was carried out by injecting labeled water into shrub roots and sampling shrubs and nearby crops for isotopic analysis of plant water. These findings build on work that was completed in 2004 at the site, but point to lower overall magnitude of diurnal soil water potential fluctuations in dry soils. Using even the limited resources that farmers possess, this agroforestry technique can be expanded over wide swaths of the Sahel.

Tree value system: users guide.

Treesearch

J.K. Ayer Sachet; D.G. Briggs; R.D. Fight

1989-01-01

This paper instructs resource analysts on use of the Tree Value System (TREEVAL). TREEVAL is a microcomputer system of programs for calculating tree or stand values and volumes based on predicted product recovery. Designed for analyzing silvicultural decisions, the system can also be used for appraisals and for evaluating log bucking. The system calculates results...

Automated rule-base creation via CLIPS-Induce

NASA Technical Reports Server (NTRS)

Murphy, Patrick M.

1994-01-01

Many CLIPS rule-bases contain one or more rule groups that perform classification. In this paper we describe CLIPS-Induce, an automated system for the creation of a CLIPS classification rule-base from a set of test cases. CLIPS-Induce consists of two components, a decision tree induction component and a CLIPS production extraction component. ID3, a popular decision tree induction algorithm, is used to induce a decision tree from the test cases. CLIPS production extraction is accomplished through a top-down traversal of the decision tree. Nodes of the tree are used to construct query rules, and branches of the tree are used to construct classification rules. The learned CLIPS productions may easily be incorporated into a large CLIPS system that perform tasks such as accessing a database or displaying information.

Tree Testing of Hierarchical Menu Structures for Health Applications

PubMed Central

Le, Thai; Chaudhuri, Shomir; Chung, Jane; Thompson, Hilaire J; Demiris, George

2014-01-01

To address the need for greater evidence-based evaluation of Health Information Technology (HIT) systems we introduce a method of usability testing termed tree testing. In a tree test, participants are presented with an abstract hierarchical tree of the system taxonomy and asked to navigate through the tree in completing representative tasks. We apply tree testing to a commercially available health application, demonstrating a use case and providing a comparison with more traditional in-person usability testing methods. Online tree tests (N=54) and in-person usability tests (N=15) were conducted from August to September 2013. Tree testing provided a method to quantitatively evaluate the information structure of a system using various navigational metrics including completion time, task accuracy, and path length. The results of the analyses compared favorably to the results seen from the traditional usability test. Tree testing provides a flexible, evidence-based approach for researchers to evaluate the information structure of HITs. In addition, remote tree testing provides a quick, flexible, and high volume method of acquiring feedback in a structured format that allows for quantitative comparisons. With the diverse nature and often large quantities of health information available, addressing issues of terminology and concept classifications during the early development process of a health information system will improve navigation through the system and save future resources. Tree testing is a usability method that can be used to quickly and easily assess information hierarchy of health information systems. PMID:24582924

Harvesting and utilization

Treesearch

A. Seki; D.L. Sirois; T. Kamen

1982-01-01

This xction explains the harvesting system selected. based upon topography, soil condition, and tree size. It is a highly mechmized, capital intensive system which includes tracked feller-bunchers to cut and bunch the trees. and trucked forwarders to transport the bunched trees to a whole tree chipper. The chips will be loaded into vans and transported to a designated...

Assessment of the GHG budget mitigation potential of intercrops: analysis on several trials and intercrops species in the Southwest of France.

NASA Astrophysics Data System (ADS)

Ferlicoq, M.; Ceschia, E.; Brut, A.; VandeWalle, A.

2012-04-01

To reduce organic carbon loss from the soil and nitrate leaching to groundwater, the European directives have promoted Good Agricultural Practices (GAP), such as the use of intercrops (IC). As shown by Béziat et al. 2009, Ceschia et al. 2010, the IC (or voluntary regrowth from the previous crop) limit net CO2 release from the ecosystem or even contribute to carbon storage during their development. However, the seeding and destruction of IC can be difficult on soil with high clay content, especially when soil is wet, and they must be destroyed early enough so that the nitrogen they contain can be released in the soil and used by the following crops. For these reasons, the Midi-Pyrenees Agriculture Department obtained a 2-year temporary derogation to test the implementation of several nitrates catch crops (mustard, diploïd oat, black oat, oat/vetch, oat/phacelia) on clay soils in order to evaluate the best management practices for growing and destroying them. Their impact on the next crop development was also analysed. In this study, the CESBIO helped the Midi-Pyrénées Agriculture Department to 1) calculate a carbon budget for the different trials and 2) to estimate GHG budgets for those trials by using a life cycle analysis (LCA) approach. Emissions associated to Field Operations (FO) were estimated based on study by Ceschia et al. (2010). During long periods of bare soil, the net CO2 flux is reduced to heterotrophic respiration. Since this component of NEE is not measured on the IC sites, it has been estimated using data from a GHG-Europe instrumented site in the same region, the same year and on similar soils (Auradé site, Gers). Heterotrophic respiration was estimated to range between 96.4 and 131 g eq-C m-2 during the IC cycle that lasted between 65 and 89 days. At the end of the IC period, biomass was (in g eq-C) 0.77, 0.18, 9.89, 0.42, 0.48 for mustard, diploïd oat, black oat, oat/vetch, oat/phacelia respectively. The low amount of biomass is explained by a very dry summer in 2009. FO ranged between 9.9 and 12.7 for the different trials. Compared to the other terms, they have a relative low impact on the GHG budget. They represented at most 13g eq-C during the IC period, 60% of those emissions are caused by the use of machinery. GHG budgets over the IC period are largely positive (source effect), due to low biomass production, mainly because of poor emergence and/or development. Still carbon fixation in the biomass mitigated the emissions. To balance the GHG budget, biomass production should be doubled for mustard (1.5 ton biomass ha-1) which is realistic and increased by a factor 4 for oat/phacelia and oat/vetch associations. In general, we can conclude that except for the black oat (biomass production is too low), these intercrops improve the GHG budget. Nevertheless, to get real advantages from these intercrops, they need to produce more than 0.26 t/ ha to compensate technical operations and additional CO2 emissions associated to IC decomposition will have to be assessed.

Object-oriented fault tree evaluation program for quantitative analyses

NASA Technical Reports Server (NTRS)

Patterson-Hine, F. A.; Koen, B. V.

1988-01-01

Object-oriented programming can be combined with fault free techniques to give a significantly improved environment for evaluating the safety and reliability of large complex systems for space missions. Deep knowledge about system components and interactions, available from reliability studies and other sources, can be described using objects that make up a knowledge base. This knowledge base can be interrogated throughout the design process, during system testing, and during operation, and can be easily modified to reflect design changes in order to maintain a consistent information source. An object-oriented environment for reliability assessment has been developed on a Texas Instrument (TI) Explorer LISP workstation. The program, which directly evaluates system fault trees, utilizes the object-oriented extension to LISP called Flavors that is available on the Explorer. The object representation of a fault tree facilitates the storage and retrieval of information associated with each event in the tree, including tree structural information and intermediate results obtained during the tree reduction process. Reliability data associated with each basic event are stored in the fault tree objects. The object-oriented environment on the Explorer also includes a graphical tree editor which was modified to display and edit the fault trees.

Automated Mobile System for Accurate Outdoor Tree Crop Enumeration Using an Uncalibrated Camera.

PubMed

Nguyen, Thuy Tuong; Slaughter, David C; Hanson, Bradley D; Barber, Andrew; Freitas, Amy; Robles, Daniel; Whelan, Erin

2015-07-28

This paper demonstrates an automated computer vision system for outdoor tree crop enumeration in a seedling nursery. The complete system incorporates both hardware components (including an embedded microcontroller, an odometry encoder, and an uncalibrated digital color camera) and software algorithms (including microcontroller algorithms and the proposed algorithm for tree crop enumeration) required to obtain robust performance in a natural outdoor environment. The enumeration system uses a three-step image analysis process based upon: (1) an orthographic plant projection method integrating a perspective transform with automatic parameter estimation; (2) a plant counting method based on projection histograms; and (3) a double-counting avoidance method based on a homography transform. Experimental results demonstrate the ability to count large numbers of plants automatically with no human effort. Results show that, for tree seedlings having a height up to 40 cm and a within-row tree spacing of approximately 10 cm, the algorithms successfully estimated the number of plants with an average accuracy of 95.2% for trees within a single image and 98% for counting of the whole plant population in a large sequence of images.

Automated Mobile System for Accurate Outdoor Tree Crop Enumeration Using an Uncalibrated Camera

PubMed Central

Nguyen, Thuy Tuong; Slaughter, David C.; Hanson, Bradley D.; Barber, Andrew; Freitas, Amy; Robles, Daniel; Whelan, Erin

2015-01-01

This paper demonstrates an automated computer vision system for outdoor tree crop enumeration in a seedling nursery. The complete system incorporates both hardware components (including an embedded microcontroller, an odometry encoder, and an uncalibrated digital color camera) and software algorithms (including microcontroller algorithms and the proposed algorithm for tree crop enumeration) required to obtain robust performance in a natural outdoor environment. The enumeration system uses a three-step image analysis process based upon: (1) an orthographic plant projection method integrating a perspective transform with automatic parameter estimation; (2) a plant counting method based on projection histograms; and (3) a double-counting avoidance method based on a homography transform. Experimental results demonstrate the ability to count large numbers of plants automatically with no human effort. Results show that, for tree seedlings having a height up to 40 cm and a within-row tree spacing of approximately 10 cm, the algorithms successfully estimated the number of plants with an average accuracy of 95.2% for trees within a single image and 98% for counting of the whole plant population in a large sequence of images. PMID:26225982

Mobilization of interactions between functional diversity of plant and soil organisms on nitrogen availability and use

NASA Astrophysics Data System (ADS)

Drut, Baptiste; Cassagne, Nathalie; Cannavacciuolo, Mario; Brauman, Alain; Le Floch, Gaëtan; Cobo, Jose; Fustec, Joëlle

2017-04-01

Keywords: legumes, earthworms, microorganisms, nitrogen, interactions Both aboveground and belowground biodiversity and their interactions can play an important role in crop productivity. Plant functional diversity, such as legume based intercrops have been shown to improve yields through plant complementarity for nitrogen use (Corre-Hellou et al., 2006). Moreover, plant species or plant genotype may influence the structure of soil microorganism communities through the composition of rhizodeposits in the rhizosphere (Dennis et al., 2010). Belowground diversity can also positively influence plant performance especially related to functional dissimilarity between soil organisms (Eisenhauer, 2012). Earthworms through their burrowing activity influence soil microbial decomposers and nutrient availability and have thus been reported to increase plant growth (Brown, 1995; Brown et al., 2004). We hypothesize that i) plant functional (genetic and/or specific) diversity associated to functional earthworms diversity are key drivers of interactions balance to improve crop performances and ii) the improvement of plant performances can be related to change in the structure of soil microorganism communities due to the diversity of rhizodeposits and the burrowing activity of earthworms. In a first mesocosm experiment, we investigated the effect of a gradient of plant diversity - one cultivar of wheat (Triticum aestivum L.), 3 different wheat cultivars, and 3 different cultivars intercropped with clover (Trifolium hybridum L.) - and the presence of one (endogeic) or two (endogeic and anecic) categories of earthworms on biomass and nitrogen accumulation of wheat. In a second mesocosm experiment, we investigated the influence of three species with different rhizodeposition - wheat, rapeseed (Brassica napus L. ) and faba bean (Vicia faba L.) in pure stand or intercropped - and the presence of endogeic earthworms on microbial activity and nitrogen availability. In the first experiment, biomass and nitrogen accumulation of wheat were improved in the presence of earthworms and clover. No effect of a plant genetic diversity was shown on crop performances. Furthermore, the influence of earthworms on bacterial diversity depended on plant diversity. In the second experiment, the specific composition of plant and earthworm presence modified the physiological profiles of rhizospheric microorganism communities (Microresp®) and nitrification potential. In the presence of faba-bean, microorganism activity was consistently increased and earthworms tended to decrease C:N ratio in the rhizospheric soil. These results confirm the interest of legume based intercrops for the complementarity in nitrogen use thanks to biological fixation. This study showed the influence of earthworms on plant nitrogen acquisition by stimulating microorganism activity and nutrient availability around the roots. We also highlighted a synergistic effect between the presence of legume and endogeic earthworms for higher plant performances. We finally hypothesized that the combined effect of rhizodeposit diversity related to plant specific composition and soil chemical properties modified by earthworm activity drives the structure and activity of microorganism communities. Brown, G.G., 1995. How do earthworms affect microfloral and faunal community diversity? Plant and Soil 170, 209-231. Brown, G.G., Edwards, C.A., Brussaard, L., 2004. How earthworms affect plant growth: burrowing into the mechanisms. Earthworm ecology 2, 13-49. Corre-Hellou, G., Fustec, J., Crozat, Y., 2006. Interspecific competition for soil N and its interaction with N2 fixation, leaf expansion and crop growth in pea-barley intercrops. Plant and Soil 282, 195-208. Dennis, P.G., Miller, A.J., Hirsch, P.R., 2010. Are root exudates more important than other sources of rhizodeposits in structuring rhizosphere bacterial communities? FEMS Microbiology Ecology 72, 313-327. Eisenhauer, N., 2012. Aboveground-belowground interactions as a source of complementarity effects in biodiversity experiments. Plant and Soil 351, 1-22.

Biodiversity can support a greener revolution in Africa

PubMed Central

Snapp, Sieglinde S.; Blackie, Malcolm J.; Gilbert, Robert A.; Bezner-Kerr, Rachel; Kanyama-Phiri, George Y.

2010-01-01

The Asian green revolution trebled grain yields through agrochemical intensification of monocultures. Associated environmental costs have subsequently emerged. A rapidly changing world necessitates sustainability principles be developed to reinvent these technologies and test them at scale. The need is particularly urgent in Africa, where ecosystems are degrading and crop yields have stagnated. An unprecedented opportunity to reverse this trend is unfolding in Malawi, where a 90% subsidy has ensured access to fertilization and improved maize seed, with substantive gains in productivity for millions of farmers. To test if economic and ecological sustainability could be improved, we preformed manipulative experimentation with crop diversity in a countrywide trial (n = 991) and at adaptive, local scales through a decade of participatory research (n = 146). Spatial and temporal treatments compared monoculture maize with legume-diversified maize that included annual and semiperennial (SP) growth habits in temporal and spatial combinations, including rotation, SP rotation, intercrop, and SP intercrop systems. Modest fertilizer intensification doubled grain yield compared with monoculture maize. Biodiversity improved ecosystem function further: SP rotation systems at half-fertilizer rates produced equivalent quantities of grain, on a more stable basis (yield variability reduced from 22% to 13%) compared with monoculture. Across sites, profitability and farmer preference matched: SP rotations provided twofold superior returns, whereas diversification of maize with annual legumes provided more modest returns. In this study, we provide evidence that in Africa, crop diversification can be effective at a countrywide scale, and that shrubby, grain legumes can enhance environmental and food security. PMID:21098285

First typology of cacao (Theobroma cacao L.) systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability.

PubMed

Suárez Salazar, Juan Carlos; Ngo Bieng, Marie Ange; Melgarejo, Luz Marina; Di Rienzo, Julio A; Casanoves, Fernando

2018-01-01

We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use. We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development. We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees. Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of forest-friendly management enhancing sustainable peace building in Colombia.

Modeling ground-based timber harvesting systems using computer simulation

Treesearch

Jingxin Wang; Chris B. LeDoux

2001-01-01

Modeling ground-based timber harvesting systems with an object-oriented methodology was investigated. Object-oriented modeling and design promote a better understanding of requirements, cleaner designs, and better maintainability of the harvesting simulation system. The model developed simulates chainsaw felling, drive-to-tree feller-buncher, swing-to-tree single-grip...

The potential of turmeric (Curcuma xanthorrhiza) in agroforestry system based on silk tree (Albizia chinensis)

NASA Astrophysics Data System (ADS)

Purnomo, D.; Budiastuti, M. S.; Sakya, A. T.; Cholid, M. I.

2018-03-01

Turmeric (Curcuma xanthorrhiza Roxb.) is a traditional medicinal plant. In Indonesia, it is generally cultivated in village home gardens. Famers conducted very simpple cultivation method of turmeric, without specific maintenance and below varies tree. The experiment was conducted by cultivating turmeric below silk trees as in agroforetry system. The experiment was arranged split plot design, the first factor was three level of irradiation (turmeric monoculture/full irradiation, turmeric below silktree with pruning canopy, and turmeric below silk tree no pruning). The second factor was fertilizer NPK 15-15-15 with three levels of doses (100, 150, and 200 kg ha-1). Cultivating turmeric in agroforestry system based on silk tree which were one year old and not yet needed pruning, application of NPK 15-15-15 fertilizer 100 kg ha-1 was enough. The rhizome yield of turmeric 3 months age reaches 139 g per plant (fresh weight). Litter fall from a silk tree one year old in one year is 30 kg per tree per year.

A System to Derive Optimal Tree Diameter Increment Models from the Eastwide Forest Inventory Data Base (EFIDB)

Treesearch

Don C. Bragg

2002-01-01

This article is an introduction to the computer software used by the Potential Relative Increment (PRI) approach to optimal tree diameter growth modeling. These DOS programs extract qualified tree and plot data from the Eastwide Forest Inventory Data Base (EFIDB), calculate relative tree increment, sort for the highest relative increments by diameter class, and...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caldwell, M.M.; Eissenstat, D.M.; Richards, J.H.

Two species of Agropyron grass differed strikingly in their capacity to compete for phosphate in soil interspaces shared with a common competitor, the sagebrush Artemisia tridentata. Of the total phosphorus-32 and -33 absorbed by Artemisia, 86% was from the interspace shared with Agropyron spicatum and only 14% from that shared with Agropyron desertorum. Actively absorbing mycorrhizal roots of Agropyron and Artemisia were present in both interspaces, where competition for the labeled phosphate occurred. The results have important implications about the way in which plants compete for resources below ground in both natural plant communities and agricultural intercropping systems.

[Effects of agricultural practices on community structure of arbuscular mycorrhizal fungi in agricultural ecosystem: a review].

PubMed

Sheng, Ping-Ping; Li, Min; Liu, Run-Jin

2011-06-01

Arbuscular mycorrhizal (AM) fungi are rich in diversity in agricultural ecosystem, playing a vital role based on their unique community structure. Host plants and environmental factors have important effects on AM fungal community structure, so do the agricultural practices which deserve to pay attention to. This paper summarized the research advances in the effects of agricultural practices such as irrigation, fertilization, crop rotation, intercropping, tillage, and pesticide application on AM fungal community structure, analyzed the related possible mechanisms, discussed the possible ways in improving AM fungal community structure in agricultural ecosystem, and put forward a set of countermeasures, i.e., improving fertilization system and related integrated techniques, increasing plant diversity in agricultural ecosystem, and inoculating AM fungi, to enhance the AM fungal diversity in agricultural ecosystem. The existing problems in current agricultural practices and further research directions were also proposed.

Estimating parameters for tree basal area growth with a system of equations and seemingly unrelated regressions

Treesearch

Charles E. Rose; Thomas B. Lynch

2001-01-01

A method was developed for estimating parameters in an individual tree basal area growth model using a system of equations based on dbh rank classes. The estimation method developed is a compromise between an individual tree and a stand level basal area growth model that accounts for the correlation between trees within a plot by using seemingly unrelated regression (...

Multifunctional Dryland Forestry: Accumulating Experience From the East-Mediterranean

NASA Astrophysics Data System (ADS)

Osem, Y.; Shachack, M.; Moshe, I.

2014-12-01

Although small in size the landscapes of East Mediterranean Israel extend over a wide geo-climatic gradient ranging from dry sub-humid to hyper-arid lands. Thousands of years under intense human exploitation in this region, involving cutting, livestock grazing, agricultural practice and fire have resulted in severe degradation of these water limited ecosystems. The highly degraded state of the native vegetation as found by the new settlers coming to Israel in the beginning of the previous century, has provided the basic motivation for an extensive afforestation enterprise carried out during the last 100 years. This talk will present an overview on the accumulating experience in establishing and managing multifunctional forests in this dryland region. Given their very limited timber value, dryland forests are designed and managed under various goals the important of which are landscape aesthetics, recreation opportunities, grazing land, ecosystem restoration and soil conservation. Being subjected to water scarcity of high temporal and spatial variation, these manmade systems are managed to withstand water deficiency of unpredictable magnitude through the manipulation of both water input and water consumption. In the dry subhumid regions, forest management focuses mainly on controlling water consumption through the manipulation of vegetation structure using thinning and livestock grazing as primary silvicultural tools. Going into the semiarid zone, practices of rainfall redistribution and runoff harvesting become crucial for tree establishment and growth. The implementation of these practices varies depending on topography, rainfall amount and forest goals. The talk will provide a brief description of these unique silvicultural systems, review some of the recent scientific work in them and refer to critical gaps in knowledge. The relevancy to intercrop agroforestry in rainfed ecosystems will be discussed.

A life cycle greenhouse gas inventory of a tree production system

Treesearch

Alissa Kendall; E. Gregory McPherson

2012-01-01

PurposeThis study provides a detailed, process-based life cycle greenhouse gas (GHG) inventory of an ornamental tree production system for urban forestry. The success of large-scale tree planting initiatives for climate protection depends on projects being net sinks for CO2 over their entire life cycle....

New Tree-Classification System Used by the Southern Forest Inventory and Analysis Unit

Treesearch

Dennis M. May; John S. Vissage; D. Vince Few

1990-01-01

Trees at USDA Forest Service, Southern Forest Inventory and Analysis, sample locations are classified as growing stock or cull based on their ability to produce sawlogs. The old and new classification systems are compared, and the impacts of the new system on the reporting of tree volumes are illustrated with inventory data from north Alabama.

First typology of cacao (Theobroma cacao L.) systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability

PubMed Central

Suárez Salazar, Juan Carlos; Melgarejo, Luz Marina; Di Rienzo, Julio A.; Casanoves, Fernando

2018-01-01

Aim and background We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use. Material and methods We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development. Main results We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees. Main conclusions and prospects Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of forest-friendly management enhancing sustainable peace building in Colombia. PMID:29401499

Design and implementation of the tree-based fuzzy logic controller.

PubMed

Liu, B D; Huang, C Y

1997-01-01

In this paper, a tree-based approach is proposed to design the fuzzy logic controller. Based on the proposed methodology, the fuzzy logic controller has the following merits: the fuzzy control rule can be extracted automatically from the input-output data of the system and the extraction process can be done in one-pass; owing to the fuzzy tree inference structure, the search spaces of the fuzzy inference process are largely reduced; the operation of the inference process can be simplified as a one-dimensional matrix operation because of the fuzzy tree approach; and the controller has regular and modular properties, so it is easy to be implemented by hardware. Furthermore, the proposed fuzzy tree approach has been applied to design the color reproduction system for verifying the proposed methodology. The color reproduction system is mainly used to obtain a color image through the printer that is identical to the original one. In addition to the software simulation, an FPGA is used to implement the prototype hardware system for real-time application. Experimental results show that the effect of color correction is quite good and that the prototype hardware system can operate correctly under the condition of 30 MHz clock rate.

A procedure for selection on marking in hardwoods

Treesearch

George R., Jr. Trimble; Joseph J. Mendel; Richard A. Kennell

1974-01-01

This method of applying individual-tree selection silviculture to hardwood stands combines silvicultural considerations with financial maturity guidelines into a tree-marking system. To develop this system it was necessary to determine rates of return based on 4/4 lumber, for many of the important Appalachian species. Trees were viewed as capital investments that...

Research on Robustness of Tree-based P2P Streaming

NASA Astrophysics Data System (ADS)

Chu, Chen; Yan, Jinyao; Ding, Kuangzheng; Wang, Xi

Research on P2P streaming media is a hot topic in the area of Internet technology. It has emerged as a promising technique. This new paradigm brings a number of unique advantages such as scalability, resilience and also effectiveness in coping with dynamics and heterogeneity. However, There are also many problems in P2P streaming media systems using traditional tree-based topology such as the bandwidth limits between parents and child nodes; node's joining or leaving has a great effect on robustness of tree-based topology. This paper will introduce a method of measuring the robustness of tree-based topology: using network measurement, we observe and record the bandwidth between all the nodes, analyses the correlation between all the sibling flows, measure the robustness of tree-based topology. And the result shows that in the Tree-based topology, the different links which have similar routing paths would share the bandwidth bottleneck, reduce the robustness of the Tree-based topology.

Tree value system: description and assumptions.

Treesearch

D.G. Briggs

1989-01-01

TREEVAL is a microcomputer model that calculates tree or stand values and volumes based on product prices, manufacturing costs, and predicted product recovery. It was designed as an aid in evaluating management regimes. TREEVAL calculates values in either of two ways, one based on optimized tree bucking using dynamic programming and one simulating the results of user-...

Estimating and validating ground-based timber harvesting production through computer simulation

Treesearch

Jingxin Wang; Chris B. LeDoux

2003-01-01

Estimating ground-based timber harvesting systems production with an object oriented methodology was investigated. The estimation model developed generates stands of trees, simulates chain saw, drive-to-tree feller-buncher, swing-to-tree single-grip harvester felling, and grapple skidder and forwarder extraction activities, and analyzes costs and productivity. It also...

Voxel-Based 3-D Tree Modeling from Lidar Images for Extracting Tree Structual Information

NASA Astrophysics Data System (ADS)

Hosoi, F.

2014-12-01

Recently, lidar (light detection and ranging) has been used to extracting tree structural information. Portable scanning lidar systems can capture the complex shape of individual trees as a 3-D point-cloud image. 3-D tree models reproduced from the lidar-derived 3-D image can be used to estimate tree structural parameters. We have proposed the voxel-based 3-D modeling for extracting tree structural parameters. One of the tree parameters derived from the voxel modeling is leaf area density (LAD). We refer to the method as the voxel-based canopy profiling (VCP) method. In this method, several measurement points surrounding the canopy and optimally inclined laser beams are adopted for full laser beam illumination of whole canopy up to the internal. From obtained lidar image, the 3-D information is reproduced as the voxel attributes in the 3-D voxel array. Based on the voxel attributes, contact frequency of laser beams on leaves is computed and LAD in each horizontal layer is obtained. This method offered accurate LAD estimation for individual trees and woody canopy trees. For more accurate LAD estimation, the voxel model was constructed by combining airborne and portable ground-based lidar data. The profiles obtained by the two types of lidar complemented each other, thus eliminating blind regions and yielding more accurate LAD profiles than could be obtained by using each type of lidar alone. Based on the estimation results, we proposed an index named laser beam coverage index, Ω, which relates to the lidar's laser beam settings and a laser beam attenuation factor. It was shown that this index can be used for adjusting measurement set-up of lidar systems and also used for explaining the LAD estimation error using different types of lidar systems. Moreover, we proposed a method to estimate woody material volume as another application of the voxel tree modeling. In this method, voxel solid model of a target tree was produced from the lidar image, which is composed of consecutive voxels that filled the outer surface and the interior of the stem and large branches. From the model, the woody material volume of any part of the target tree can be directly calculated easily by counting the number of corresponding voxels and multiplying the result by the per-voxel volume.

Rapid decision support tool based on novel ecosystem service variables for retrofitting of permeable pavement systems in the presence of trees.

PubMed

Scholz, Miklas; Uzomah, Vincent C

2013-08-01

The retrofitting of sustainable drainage systems (SuDS) such as permeable pavements is currently undertaken ad hoc using expert experience supported by minimal guidance based predominantly on hard engineering variables. There is a lack of practical decision support tools useful for a rapid assessment of the potential of ecosystem services when retrofitting permeable pavements in urban areas that either feature existing trees or should be planted with trees in the near future. Thus the aim of this paper is to develop an innovative rapid decision support tool based on novel ecosystem service variables for retrofitting of permeable pavement systems close to trees. This unique tool proposes the retrofitting of permeable pavements that obtained the highest ecosystem service score for a specific urban site enhanced by the presence of trees. This approach is based on a novel ecosystem service philosophy adapted to permeable pavements rather than on traditional engineering judgement associated with variables based on quick community and environment assessments. For an example case study area such as Greater Manchester, which was dominated by Sycamore and Common Lime, a comparison with the traditional approach of determining community and environment variables indicates that permeable pavements are generally a preferred SuDS option. Permeable pavements combined with urban trees received relatively high scores, because of their great potential impact in terms of water and air quality improvement, and flood control, respectively. The outcomes of this paper are likely to lead to more combined permeable pavement and tree systems in the urban landscape, which are beneficial for humans and the environment. Copyright © 2013 Elsevier B.V. All rights reserved.

Modeling of air pollutant removal by dry deposition to urban trees using a WRF/CMAQ/i-Tree Eco coupled system.

PubMed

Cabaraban, Maria Theresa I; Kroll, Charles N; Hirabayashi, Satoshi; Nowak, David J

2013-05-01

A distributed adaptation of i-Tree Eco was used to simulate dry deposition in an urban area. This investigation focused on the effects of varying temperature, LAI, and NO2 concentration inputs on estimated NO2 dry deposition to trees in Baltimore, MD. A coupled modeling system is described, wherein WRF provided temperature and LAI fields, and CMAQ provided NO2 concentrations. A base case simulation was conducted using built-in distributed i-Tree Eco tools, and simulations using different inputs were compared against this base case. Differences in land cover classification and tree cover between the distributed i-Tree Eco and WRF resulted in changes in estimated LAI, which in turn resulted in variations in simulated NO2 dry deposition. Estimated NO2 removal decreased when CMAQ-derived concentration was applied to the distributed i-Tree Eco simulation. Discrepancies in temperature inputs did little to affect estimates of NO2 removal by dry deposition to trees in Baltimore. Copyright © 2013 Elsevier Ltd. All rights reserved.

A GIS-based tool for estimating tree canopy cover on fixed-radius plots using high-resolution aerial imagery

Treesearch

Sara A. Goeking; Greg C. Liknes; Erik Lindblom; John Chase; Dennis M. Jacobs; Robert. Benton

2012-01-01

Recent changes to the Forest Inventory and Analysis (FIA) Program's definition of forest land precipitated the development of a geographic information system (GIS)-based tool for efficiently estimating tree canopy cover for all FIA plots. The FIA definition of forest land has shifted from a density-related criterion based on stocking to a 10 percent tree canopy...

The Historical, Environmental and Socio-Economic Context of Forests and Tree-Based Systems for Food Security and Nutrition (Chapter 3)

Treesearch

John A. Parrotta; Jennie Dey de Pryck; Beatrice Darko Obiri; Christine Padoch; Bronwen Powell; Chris Sandbrook

2015-01-01

Forests and tree-based systems are an important component of rural landscapes, sustaining livelihoods and contributing to the food security and nutritional needs of hundreds of millions of people worldwide. Historically, these systems developed under a wide variety of ecological conditions, and cultural and socio-economic contexts, as integrated approaches that...

Carbon Sequestration Estimation of Street Trees Based on Point Cloud from Vehicle-Borne Laser Scanning System

NASA Astrophysics Data System (ADS)

Zhao, Y.; Hu, Q.

2017-09-01

Continuous development of urban road traffic system requests higher standards of road ecological environment. Ecological benefits of street trees are getting more attention. Carbon sequestration of street trees refers to the carbon stocks of street trees, which can be a measurement for ecological benefits of street trees. Estimating carbon sequestration in a traditional way is costly and inefficient. In order to solve above problems, a carbon sequestration estimation approach for street trees based on 3D point cloud from vehicle-borne laser scanning system is proposed in this paper. The method can measure the geometric parameters of a street tree, including tree height, crown width, diameter at breast height (DBH), by processing and analyzing point cloud data of an individual tree. Four Chinese scholartree trees and four camphor trees are selected for experiment. The root mean square error (RMSE) of tree height is 0.11m for Chinese scholartree and 0.02m for camphor. Crown widths in X direction and Y direction, as well as the average crown width are calculated. And the RMSE of average crown width is 0.22m for Chinese scholartree and 0.10m for camphor. The last calculated parameter is DBH, the RMSE of DBH is 0.5cm for both Chinese scholartree and camphor. Combining the measured geometric parameters and an appropriate carbon sequestration calculation model, the individual tree's carbon sequestration will be estimated. The proposed method can help enlarge application range of vehicle-borne laser point cloud data, improve the efficiency of estimating carbon sequestration, construct urban ecological environment and manage landscape.

MTVis: tree exploration using a multitouch interface

NASA Astrophysics Data System (ADS)

Andrews, David; Teoh, Soon Tee

2010-01-01

We present MTVis, a multi-touch interactive tree visualization system. The multi-touch interface display hardware is built using the LED-LP technology, and the tree layout is based on RINGS, but enhanced with multitouch interactions. We describe the features of the system, and how the multi-touch interface enhances the user's experience in exploring the tree data structure. In particular, the multi-touch interface allows the user to simultaneously control two child nodes of the root, and rotate them so that some nodes are magnified, while preserving the layout of the tree. We also describe the other meaninful touch screen gestures the users can use to intuitively explore the tree.

Semiautomated landscape feature extraction and modeling

NASA Astrophysics Data System (ADS)

Wasilewski, Anthony A.; Faust, Nickolas L.; Ribarsky, William

2001-08-01

We have developed a semi-automated procedure for generating correctly located 3D tree objects form overhead imagery. Cross-platform software partitions arbitrarily large, geocorrected and geolocated imagery into management sub- images. The user manually selected tree areas from one or more of these sub-images. Tree group blobs are then narrowed to lines using a special thinning algorithm which retains the topology of the blobs, and also stores the thickness of the parent blob. Maxima along these thinned tree grous are found, and used as individual tree locations within the tree group. Magnitudes of the local maxima are used to scale the radii of the tree objects. Grossly overlapping trees are culled based on a comparison of tree-tree distance to combined radii. Tree color is randomly selected based on the distribution of sample tree pixels, and height is estimated form tree radius. The final tree objects are then inserted into a terrain database which can be navigated by VGIS, a high-resolution global terrain visualization system developed at Georgia Tech.

Banana production systems: identification of alternative systems for more sustainable production.

PubMed

Bellamy, Angelina Sanderson

2013-04-01

Large-scale, monoculture production systems dependent on synthetic fertilizers and pesticides, increase yields, but are costly and have deleterious impacts on human health and the environment. This research investigates variations in banana production practices in Costa Rica, to identify alternative systems that combine high productivity and profitability, with reduced reliance on agrochemicals. Farm workers were observed during daily production activities; 39 banana producers and 8 extension workers/researchers were interviewed; and a review of field experiments conducted by the National Banana Corporation between 1997 and 2002 was made. Correspondence analysis showed that there is no structured variation in large-scale banana producers' practices, but two other banana production systems were identified: a small-scale organic system and a small-scale conventional coffee-banana intercropped system. Field-scale research may reveal ways that these practices can be scaled up to achieve a productive and profitable system producing high-quality export bananas with fewer or no pesticides.

Herbage intake, methane emissions and animal performance of steers grazing dwarf elephant grass v. dwarf elephant grass and peanut pastures.

PubMed

Andrade, E A; Almeida, E X; Raupp, G T; Miguel, M F; de Liz, D M; Carvalho, P C F; Bayer, C; Ribeiro-Filho, H M N

2016-10-01

Management strategies for increasing ruminant legume consumption and mitigating methane emissions from tropical livestock production systems require further study. The aim of this work was to evaluate the herbage intake, animal performance and enteric methane emissions of cattle grazing dwarf elephant grass (DEG) (Pennisetum purpureum cv. BRS Kurumi) alone or DEG with peanut (Arachis pintoi cv. Amarillo). The experimental treatments were the following: DEG pastures receiving nitrogen fertilization (150 kg N/ha as ammonium nitrate) and DEG intercropped with peanut plus an adjacent area of peanut that was accessible to grazing animals for 5 h/day (from 0700 to 1200 h). The animals grazing legume pastures showed greater average daily gain and herbage intake, and shorter morning and total grazing times. Daily methane emissions were greater from the animals grazing legume pastures, whereas methane emissions per unit of herbage intake did not differ between treatments. Allowing animals access to an exclusive area of legumes in a tropical grass-pasture-based system can improve animal performance without increasing methane production per kg of dry matter intake.

Multiplying Forest Garden Systems with biochar based organic fertilization for high carbon accumulation, improved water storage, nutrient cycling, and increased food diversity and farm productivity

NASA Astrophysics Data System (ADS)

Schmidt, Hans-Peter; Pandit, Bishnu Hari; Lucht, Wolfgang; Gerten, Dieter; Kammann, Claudia

2017-04-01

On abandoned, erosion prone terraces in the middle hills of Nepal, 86 participating farmer families planted >25,000 mixed trees in 2015/16. Since it was convincingly demonstrated by more than 20 field trials in this region that this was the most plant-growth promoting method, all trees were planted with farmer-made organic biochar-based fertilizer. Planting pits were mulched with rice straw and were pipe irrigated from newly established water retention ponds during the 7 months of the dry season. A peer control system of farmer triads ensured an efficient maintenance of the plantations. Tree survival rate was above 80% after one year compared to below 50% on average for countrywide forestation projects over the last 30 years. In between the young Cinnamon, Moringa, Mulberry, Lemon, Michelia, Paulownia, nut and other trees, other secondary crops were cultivated such as ginger, turmeric, black beans, onions, lentils, all with organic biochar-based fertilizer and mulching. The objective of this forest garden project was to establish robust social-agronomic systems that can be multiplied from village to village for increasing soil fertility, protecting abandoned terraces from erosion, replenishing natural water resources, generating a stable income with climate-smart agriculture, as well as capturing and sequestering atmospheric carbon. The initial financing of the set-up of the forest garden systems (tree nursery, plantation, preparation of organic biochar based fertilizer, mulching materials, building of irrigation pits and pipe irrigation system, and general maintenance) was covered by carbon credits paid in advance by the international community in the form of a monthly carbon compensation subscription. All planted trees are GIS inventoried and the yearly biomass carbon uptake will be calculated as an average value of the first ten years of tree growth. The 25,000 mixed trees accumulated the equivalent of 350 t CO2 per year (10 years total C-accumulation divided by 10 years). Besides covering the set-up costs, farmers received and continue to receive carbon payments for each survived tree during the first three years. Based on a voluntary carbon credit price of 35 USD per t CO2, the annual income of the farmers increase by 6 to 13% depending on their poverty level. After this initial period of three years, the income from tree crops (fruits, nuts, medicine, essential oil, silk, perfume, honey, timber, animal fodder) exceeds by far the (catalyzer) carbon credits (average crop income for the 25,000 trees including secondary mixed cropping > 150,000 USD). The trees will accumulate carbon for 15 to 75 years depending on the tree species. While trunk wood will be used for construction timber and thus continue to sequester carbon for probably 50 years. While part of the wood will be used for cooking, at least 50% of the tree biomass will be pyrolyzed to biochar to produce organic biochar-based fertilizers and for using the pyrolysis heat for the production of essential oil, pasteurization and fruit or tea leaves drying. Compared to the barren terraces, sparsely covered with grasses and prone to erosion, the forest garden system with organic biochar-based fertilizer, continuous soil cover, mulching, leaf litter fall, root growth and root exudates, rotating cover crops and animal pasture, soil organic carbon (SOC) is expected to increase annually. Therefore, for each participating farmer at least one land spot is GIS marked for soil organic carbon analysis to be executed every five years and to calculate and certify soil organic carbon increases for additional or bonus carbon credits. In our presentation we will show and document the establishment of the forest garden systems, and discuss the link between local carbon sequestration and global carbon markets, the carbon calculation and certification procedures, and the challenge for multiplying such systems inter-regional and internationally.

Effect of green manure in soil quality and nitrogen transfer to cherry tomato in the no tillage system

NASA Astrophysics Data System (ADS)

Ambrosano, Edmilson; Rossi, Fabricio; Dias, Fabio; Trivelin, Paulo; Tavares, Silvio; Muraoka, Takashi; Ambrosano, Glaucia; Salgado, Gabriela; Otsuk, Ivani

2016-04-01

The use of alternative fertilizers may reduce costs and promote sustainability to the family-based agro ecological production system. The objective of this study was to quantify the contribution of the green manure to the quality of the soil and the transference of the nitrogen to cherry tomatoes using the N-15 abundance method (FAPESP 11/05648-3). The experiment was carried out in Piracicaba, APTA/SAA, SP, Brazil. The IAC collection accesses 21 of cherry tomatoes were used. Each Plot consisted of six plants spaced 0.5 m and 0.9 m between rows, using a randomized-blocks design with eight treatments and five repetitions. The treatments consisted of green manure crops intercropped or not with cherry tomato, namely: jack bean (Canavalia ensiformis), sunn hemp (Crotalaria juncea L.), velvet bean (Mucuna deeringiana), mung bean (Vigna radiata (L.) Wilczek), white lupine (Lupinus albus L.) and cowpea (Vigna unguiculata (L.) Walp). Besides two witnesses, one with and another without corn straw. Five leaves with petiole of each plant part from the first ripe fruit and a bunch of fruits per plant are harvested. Samples of leaf and fruit were weighed and dried in a forced air oven and its dry weight measured. A subsample was ground in a Wiley mill and brought to the mass spectrometer (ANCA GSL) on the Stable Isotopes Laboratory of CENA/USP for δN-15 analysis. It measured the percentage of the transference of N from the green manure to the tomato; the tomato plants grown in monocropping were considered a control. It was found that 27 % of the N present in the fruit and 23% of the N present in the leaves came from the green manure. These results show that dur¬ing the development of the fruit of the tomato there is a greater translocation and consequently, a higher use of the N from the green manure in the fruits than in the leaves. This production system can reduce the use of nitrogen fertilizers. The presence of a green manure in non-intercropped treatments caused some soil alterations that could be detected in samples collected in the harvesting season. There was an increase in organic matter, Ca, Mg and Zn availability and consequently, in the base saturation and in the pH. The presence of green manure caused a significant increase in the sum of bases, due to increases in calcium and magnesium; consequently, treatments involving jack bean, sunn hemp and mung bean showed higher CEC values and low acidity potential. The presence of organic acids in the plant mass could be the reason for this change. The use of green manure also increases the carbon sequestration, contributing to the reduction of the greenhouse effect.

Application of CarboSOIL model to predict the effects of climate change on soil organic carbon stocks in agro-silvo-pastoral Mediterranean management systems

NASA Astrophysics Data System (ADS)

Muñoz-Rojas, Miriam; Doro, Luca; Ledda, Luigi; Francaviglia, Rosa

2014-05-01

CarboSOIL is an empirical model based on regression techniques and developed to predict soil organic carbon contents (SOC) at standard soil depths of 0-25, 25-50 and 50-75 cm (Muñoz-Rojas et al., 2013). The model was applied to a study area of north-eastern Sardinia (Italy) (40° 46'N, 9° 10'E, mean altitude 285 m a.s.l.), characterized by extensive agro-silvo-pastoral systems which are typical of similar areas of the Mediterranean basin (e.g. the Iberian peninsula). The area has the same soil type (Haplic Endoleptic Cambisols, Dystric according to WRB), while cork oak forest (Quercus suber L.) is the potential native vegetation which has been converted to managed land with pastures and vineyards in recent years (Lagomarsino et al., 2011; Francaviglia et al., 2012; Bagella et al, 2013; Francaviglia et al., 2014). Six land uses with different levels of cropping intensification were compared: Tilled vineyards (TV); No-tilled grassed vineyards (GV); Hay crop (HC); Pasture (PA); Cork oak forest (CO) and Semi-natural systems (SN). The HC land use includes oats, Italian ryegrass and annual clovers or vetch for 5 years and intercropped by spontaneous herbaceous vegetation in the sixth year. The PA land use is 5 years of spontaneous herbaceous vegetation, and one year of intercropping with oats, Italian ryegrass and annual clovers or vetch cultivated as a hay crop. The SN land use (scrublands, Mediterranean maquis and Helichrysum meadows) arise from the natural re-vegetation of former vineyards which have been set-aside probably due to the low grape yields and the high cost of modern tillage equipment. Both PA and HC are grazed for some months during the year, and include scattered cork-oak trees, which are key components of the 'Dehesa'-type landscape (grazing system with Quercus L.) typical of this area of Sardinia and other areas of southern Mediterranean Europe. Dehesas are often converted to more profitable land uses such as vineyards (Francaviglia et al., 2012; Muñoz-Rojas et al., 2012) or olive groves (Lozano-García and Parras-Alcántara, 2013). The local climate is warm temperate with dry and hot summers, with a mean annual rainfall of 623 mm (range 367-811 mm) and mean annual temperature of 15.0?C (13.8-16.4?C). Climate change scenarios were generated from the baseline climate with two Global Climate Models: GISS (Goddard Institute of Space Studies, USA), and HadCM3 (Met Office, Hadley Centre, UK), for two of the Intergovernmental Panel on Climate Change (IPCC) emission scenarios (A2 and B2). Three time horizons were chosen for climate change projections: 2020, mean climate change for the period 2010-2039; 2050 for the period 2040-2069; and 2080 for the period 2070-2099, providing respectively a very close, an intermediate, and a fully realized climate change scenario. The agreement of model predictions with the measured values of soil organic carbon stocks was tested using the correlation coefficient R2, the root mean square error RMSE and the modelling efficiency EF. For a good model performance, RMSE should have approximately the same order of magnitude of the standard deviation, while EF should be positive and close to 1. With reference to the three soil depths (0-25, 25-50, 50-75 cm), R2, RMSE and EF are in the range 0.76-0.99, 5.07-8.42, and 0.63-0.98 respectively. CarboSOIL predictions are fully acceptable since the linear regression coefficients are always significant at p

A new method of optimal capacitor switching based on minimum spanning tree theory in distribution systems

NASA Astrophysics Data System (ADS)

Li, H. W.; Pan, Z. Y.; Ren, Y. B.; Wang, J.; Gan, Y. L.; Zheng, Z. Z.; Wang, W.

2018-03-01

According to the radial operation characteristics in distribution systems, this paper proposes a new method based on minimum spanning trees method for optimal capacitor switching. Firstly, taking the minimal active power loss as objective function and not considering the capacity constraints of capacitors and source, this paper uses Prim algorithm among minimum spanning trees algorithms to get the power supply ranges of capacitors and source. Then with the capacity constraints of capacitors considered, capacitors are ranked by the method of breadth-first search. In term of the order from high to low of capacitor ranking, capacitor compensation capacity based on their power supply range is calculated. Finally, IEEE 69 bus system is adopted to test the accuracy and practicality of the proposed algorithm.

A Three-Step Approach To Model Tree Mortality in the State of Georgia

Treesearch

Qingmin Meng; Chris J. Cieszewski; Roger C. Lowe; Michal Zasada

2005-01-01

Tree mortality is one of the most complex phenomena of forest growth and yield. Many types of factors affect tree mortality, which is considered difficult to predict. This study presents a new systematic approach to simulate tree mortality based on the integration of statistical models and geographical information systems. This method begins with variable preselection...

Interacting with mobile devices by fusion eye and hand gestures recognition systems based on decision tree approach

NASA Astrophysics Data System (ADS)

Elleuch, Hanene; Wali, Ali; Samet, Anis; Alimi, Adel M.

2017-03-01

Two systems of eyes and hand gestures recognition are used to control mobile devices. Based on a real-time video streaming captured from the device's camera, the first system recognizes the motion of user's eyes and the second one detects the static hand gestures. To avoid any confusion between natural and intentional movements we developed a system to fuse the decision coming from eyes and hands gesture recognition systems. The phase of fusion was based on decision tree approach. We conducted a study on 5 volunteers and the results that our system is robust and competitive.

Cover crops do not increase C sequestration in production crops: evidence from 12 years of continuous measurements

NASA Astrophysics Data System (ADS)

Buysse, Pauline; Bodson, Bernard; Debacq, Alain; De Ligne, Anne; Heinesch, Bernard; Manise, Tanguy; Moureaux, Christine; Aubinet, Marc

2017-04-01

The numerous reports on carbon (C) loss from cropland soils have recently raised awareness on the climate change mitigation potential of these ecosystems, and on the necessity to improve C sequestration in these soils. Among the multiple solutions that are proposed, several field measurement and modelling studies reported that growing cover crops over fall and winter time could appear as an efficient solution. However, while the large majority of these studies are based on SOC stock inventories and very few information exists from the CO2 flux dynamics perspective. In the present work, we use the results from long-term (12 years) eddy-covariance measurements performed at the Lonzée Terrestrial Observatory (LTO, candidate ICOS site, Belgium) and focus on six intercrop periods managed with (3) and without (3) cover crops after winter wheat main crops, in order to compare their response to environmental factors and to investigate the impact of cover crops on Net Ecosystem Exchange (NEE). Our results showed that cumulated NEE was not significantly affected by the presence of cover crops. Indeed, while larger CO2 assimilation occurred during cover crop growth, this carbon gain was later lost by larger respiration rates due to larger crop residue amounts brought to the soil. As modelled by a Q10-like relationship, significantly larger R10 values were indeed observed during the three intercrop periods cultivated with cover crops. These CO2 flux-based results therefore tend to moderate the generally acknowledged positive impact of cover crops on net C sequestration by croplands. Our results indicate that the effect of growing cover crops on C sequestration could be less important than announced, at least at certain sites.

Farm-scale costs and returns for second generation bioenergy cropping systems in the US Corn Belt

NASA Astrophysics Data System (ADS)

Manatt, Robert K.; Hallam, Arne; Schulte, Lisa A.; Heaton, Emily A.; Gunther, Theo; Hall, Richard B.; Moore, Ken J.

2013-09-01

While grain crops are meeting much of the initial need for biofuels in the US, cellulosic or second generation (2G) materials are mandated to provide a growing portion of biofuel feedstocks. We sought to inform development of a 2G crop portfolio by assessing the profitability of novel cropping systems that potentially mitigate the negative effects of grain-based biofuel crops on food supply and environmental quality. We analyzed farm-gate costs and returns of five systems from an ongoing experiment in central Iowa, USA. The continuous corn cropping system was most profitable under current market conditions, followed by a corn-soybean rotation that incorporated triticale as a 2G cover crop every third year, and a corn-switchgrass system. A novel triticale-hybrid aspen intercropping system had the highest yields over the long term, but could only surpass the profitability of the continuous corn system when biomass prices exceeded foreseeable market values. A triticale/sorghum double cropping system was deemed unviable. We perceive three ways 2G crops could become more cost competitive with grain crops: by (1) boosting yields through substantially greater investment in research and development, (2) increasing demand through substantially greater and sustained investment in new markets, and (3) developing new schemes to compensate farmers for environmental benefits associated with 2G crops.

Soil-Atmosphere Greenhouse Gas Fluxes on the Margins of the Congo Forest: Effects of Forest Conversion towards Smallholder Agricultural Lands and Agricultural Intensification

NASA Astrophysics Data System (ADS)

kwatcho Kengdo, S.; Sonwa, D. J.; Njine-Bememba, C. B.; Djatsa, L. D.; Rufino, M. C.; Verchot, L. V.; Tejedor, J.; Dannenmann, M.

2016-12-01

The forests of the Congo Basin are subject to deforestation and land use change, which may severely influence the soil-atmosphere exchange of greenhouse gases (GHG). However, due to absence of analytical capacities in Central Africa, there is a lack of knowledge on fluxes of CO2, CH4 and N2O at the soil-atmosphere interface for natural and managed ecosystems, which introduces large uncertainties into regional and national GHG reporting. The objectives of this study were to quantify GHG emissions from typical land use on the margins of the Congo forests, to analyze seasonal variability and environmental controls of soil-atmosphere GHG fluxes across a land use gradient and explore options of sustainable intensification of maize cultivation. In Cameroon, we quantified fluxes of CO2, CH4, and N2O at the soil - atmosphere interface in secondary forests, cocoa agroforests, unfertilized mixed crop fields, and three different types of maize cultivation: unfertilized control, maize intercropped with N fixing beans, maize applied with mineral nitrogen fertilizer. We used manual static chamber techniques with approximately weekly temporal resolution over a full year and analyzed gas samples using a gas chromatograph. Soil temperature and moisture data were permanently recorded at main sites and soil sampling provided information on soil mineral N content. We found highest CO2 and N2O emissions, net CH4 uptake and soil mineral N concentrations in the secondary forest with lower values observed in cocoa agroforest and in particular in extensive mixed crop. Soil moisture changes were the dominant driver of seasonal changes of GHG fluxes at all study sites. Intercropping with N fixing beans did not alter soil N2O emissions from maize fields. In contrast, application of mineral N increased soil N2O emissions by more than a factor of five. Our work highlights the importance of soil moisture as the driver of GHG fluxes and in particular for N2O indicates a strong decrease in soil emissions after forest conversion to extensive crop fields. Agricultural intensification based on mineral N fertilizer can increase N2O emissions to levels significantly higher than those observed in secondary forests. Our trial with intercropped N fixing beans show promise towards a sustainable intensification of agriculture in the study region.

Tree growth visualization

Treesearch

L. Linsen; B.J. Karis; E.G. McPherson; B. Hamann

2005-01-01

In computer graphics, models describing the fractal branching structure of trees typically exploit the modularity of tree structures. The models are based on local production rules, which are applied iteratively and simultaneously to create a complex branching system. The objective is to generate three-dimensional scenes of often many realistic- looking and non-...

Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input.

PubMed

Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman; Ambus, Per; Boelt, Birte; Gislum, René

2016-01-15

A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t above ground dry matter ha(-1) year(-1) saving around 325 kg mineral Nfertilizer ha(-1) compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3t DM more than red clover in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground production across the three-season rotation, the pure stand red clover without N application and pure stand ryegrass treatments with the highest N input equalled. The present study illustrate how leguminous biological nitrogen fixation (BNF) represents an important low impact renewable N source without reducing crop yields and thereby farmers earnings. Copyright © 2015. Published by Elsevier B.V.

Visual tree grading systems for estimating lumber yields in young and mature southern pine

Treesearch

Alexander Clark; Robert H. McAlister

1998-01-01

New visual tree grading systems for mature southern pine ? 35 years old and young pine ? 35 years old based on number and size of branches in the lower bole are described. A series of lumber grade yield studies was conducted to test the new grading rules. A total of 214 natural loblolly pine (Pinus taeda L.) and shortleaf pine (P. echinata Mill) trees 9 to 20 inches...

Parallel object-oriented decision tree system

DOEpatents

Kamath,; Chandrika, Cantu-Paz [Dublin, CA; Erick, [Oakland, CA

2006-02-28

A data mining decision tree system that uncovers patterns, associations, anomalies, and other statistically significant structures in data by reading and displaying data files, extracting relevant features for each of the objects, and using a method of recognizing patterns among the objects based upon object features through a decision tree that reads the data, sorts the data if necessary, determines the best manner to split the data into subsets according to some criterion, and splits the data.

Quantification and identification of lightning damage in tropical forests.

PubMed

Yanoviak, Stephen P; Gora, Evan M; Burchfield, Jeffrey M; Bitzer, Phillip M; Detto, Matteo

2017-07-01

Accurate estimates of tree mortality are essential for the development of mechanistic forest dynamics models, and for estimating carbon storage and cycling. However, identifying agents of tree mortality is difficult and imprecise. Although lightning kills thousands of trees each year and is an important agent of mortality in some forests, the frequency and distribution of lightning-caused tree death remain unknown for most forests. Moreover, because all evidence regarding the effects of lightning on trees is necessarily anecdotal and post hoc, rigorous tests of hypotheses regarding the ecological effects of lightning are impossible. We developed a combined electronic sensor/camera-based system for the location and characterization of lightning strikes to the forest canopy in near real time and tested the system in the forest of Barro Colorado Island, Panama. Cameras mounted on towers provided continuous video recordings of the forest canopy that were analyzed to determine the locations of lightning strikes. We used a preliminary version of this system to record and locate 18 lightning strikes to the forest over a 3-year period. Data from field surveys of known lightning strike locations (obtained from the camera system) enabled us to develop a protocol for reliable, ground-based identification of suspected lightning damage to tropical trees. In all cases, lightning damage was relatively inconspicuous; it would have been overlooked by ground-based observers having no knowledge of the event. We identified three types of evidence that can be used to consistently identify lightning strike damage in tropical forests: (1) localized and directionally biased branch mortality associated with flashover among tree and sapling crowns, (2) mortality of lianas or saplings near lianas, and (3) scorched or wilting epiphytic and hemiepiphytic plants. The longitudinal trunk scars that are typical of lightning-damaged temperate trees were never observed in this study. Given the prevalence of communications towers worldwide, the lightning detection system described here could be implemented in diverse forest types. Data from multiple systems would provide an outstanding opportunity for comparative research on the ecological effects of lightning. Such comparative data are increasingly important given expected increases in lightning frequency with climatic change.

Mating System and Effective Population Size of the Overexploited Neotropical Tree (Myroxylon peruiferum L.f.) and Their Impact on Seedling Production.

PubMed

Silvestre, Ellida de Aguiar; Schwarcz, Kaiser Dias; Grando, Carolina; de Campos, Jaqueline Bueno; Sujii, Patricia Sanae; Tambarussi, Evandro Vagner; Macrini, Camila Menezes Trindade; Pinheiro, José Baldin; Brancalion, Pedro Henrique Santin; Zucchi, Maria Imaculada

2018-03-16

The reproductive system of a tree species has substantial impact on genetic diversity and structure within and among natural populations. Such information, should be considered when planning tree planting for forest restoration. Here, we describe the mating system and genetic diversity of an overexploited Neotropical tree, Myroxylon peruiferum L.f. (Fabaceae) sampled from a forest remnant (10 seed trees and 200 seeds) and assess whether the effective population size of nursery-grown seedlings (148 seedlings) is sufficient to prevent inbreeding depression in reintroduced populations. Genetic analyses were performed based on 8 microsatellite loci. M. peruiferum presented a mixed mating system with evidence of biparental inbreeding (t^m-t^s = 0.118). We found low levels of genetic diversity for M. peruiferum species (allelic richness: 1.40 to 4.82; expected heterozygosity: 0.29 to 0.52). Based on Ne(v) within progeny, we suggest a sample size of 47 seed trees to achieve an effective population size of 100. The effective population sizes for the nursery-grown seedlings were much smaller Ne = 27.54-34.86) than that recommended for short term Ne ≥ 100) population conservation. Therefore, to obtain a reasonable genetic representation of native tree species and prevent problems associated with inbreeding depression, seedling production for restoration purposes may require a much larger sampling effort than is currently used, a problem that is further complicated by species with a mixed mating system. This study emphasizes the need to integrate species reproductive biology into seedling production programs and connect conservation genetics with ecological restoration.

Distributed smoothed tree kernel for protein-protein interaction extraction from the biomedical literature

PubMed Central

Murugesan, Gurusamy; Abdulkadhar, Sabenabanu; Natarajan, Jeyakumar

2017-01-01

Automatic extraction of protein-protein interaction (PPI) pairs from biomedical literature is a widely examined task in biological information extraction. Currently, many kernel based approaches such as linear kernel, tree kernel, graph kernel and combination of multiple kernels has achieved promising results in PPI task. However, most of these kernel methods fail to capture the semantic relation information between two entities. In this paper, we present a special type of tree kernel for PPI extraction which exploits both syntactic (structural) and semantic vectors information known as Distributed Smoothed Tree kernel (DSTK). DSTK comprises of distributed trees with syntactic information along with distributional semantic vectors representing semantic information of the sentences or phrases. To generate robust machine learning model composition of feature based kernel and DSTK were combined using ensemble support vector machine (SVM). Five different corpora (AIMed, BioInfer, HPRD50, IEPA, and LLL) were used for evaluating the performance of our system. Experimental results show that our system achieves better f-score with five different corpora compared to other state-of-the-art systems. PMID:29099838

Distributed smoothed tree kernel for protein-protein interaction extraction from the biomedical literature.

PubMed

Murugesan, Gurusamy; Abdulkadhar, Sabenabanu; Natarajan, Jeyakumar

2017-01-01

Automatic extraction of protein-protein interaction (PPI) pairs from biomedical literature is a widely examined task in biological information extraction. Currently, many kernel based approaches such as linear kernel, tree kernel, graph kernel and combination of multiple kernels has achieved promising results in PPI task. However, most of these kernel methods fail to capture the semantic relation information between two entities. In this paper, we present a special type of tree kernel for PPI extraction which exploits both syntactic (structural) and semantic vectors information known as Distributed Smoothed Tree kernel (DSTK). DSTK comprises of distributed trees with syntactic information along with distributional semantic vectors representing semantic information of the sentences or phrases. To generate robust machine learning model composition of feature based kernel and DSTK were combined using ensemble support vector machine (SVM). Five different corpora (AIMed, BioInfer, HPRD50, IEPA, and LLL) were used for evaluating the performance of our system. Experimental results show that our system achieves better f-score with five different corpora compared to other state-of-the-art systems.

Effect of green manure in soil quality and nitrogen transfer to cherry tomato in the no tillage system on corn straw

NASA Astrophysics Data System (ADS)

Ambrosano, Edmilson; Rossi, Fabricio; Dias, Fabio; Trivelin, Paulo; Muraoka, Takashi; Tavares, Silvio; Ambrosano, Glaucia

2015-04-01

The objective of this study was to quantify the contribution of green manure in on soil quality and nitrogen transfer to cherry tomatoes using the N-15 abundance method. The experiment was carried out in Piracicaba, APTA/SAA, SP, Brazil. The IAC collection accesses 21 of cherry tomatoes were used. Each Plot consisted of six plants spaced 0.5 m and 0.9 m between rows, conducted in a randomized block with eight treatments and five repetitions. The treatments were as green manures intercropping or not on cherry tomato, namely: jack bean (Canavalia ensiformis), sunn hemp (Crotalaria juncea L.), dwarf mucuna (Mucuna deeringiana), mung bean (Vigna radiata (L.) Wilczek ), white lupine (Lupinus albus L.) and cowpea (Vigna unguiculata (L.) Walp). Besides two witnesses, one without corn straw and another with corn straw. Five leaves with petiole of each plant part during the first ripe fruit and a bunch of fruits per plant are harvested. Samples of leaf and fruit were weighed and dried in an oven of forced air and its dry weight measured. A subsample was ground in a knife mill type Willy and brought to the mass spectrometer (ANCA GSL) on the Stable Isotopes Laboratory of CENA/USP for the analysis of δN-15. It measured the percentage of transfer of N green manure for tomato, the tomato plants grown as monocropped were considered a control and came to the result that 27 % N found in the fruit came from the green manure and the aerial part this figure was 23%. These results show that dur¬ing the fruit set of tomato can occur greater translocation and consequent higher utilization of N from green manure than in the aerial part. This production system can reduce the use of nitrogen fertilizers. The presence of a green manure in treatments not intercropped caused some soil alterations that could be detected in samples collected in the harvesting season. There was an increase in organic matter, Ca, Mg and Zn availability, and consequently in base saturation and pH. The presence of green manure caused a significant sum of bases increase, due to increases in calcium and magnesium; consequently, treatments involving jack bean, sunn hemp and mung bean showed higher CEC values and low acidity potential. The presence of organic acids in the plant mass could be the reason for this change. The use of green manure also works on carbon sequestration, helping in the reduction of the greenhouse gas effect.

Product Support Manager Guidebook

DTIC Science & Technology

2011-04-01

package is being developed using supportability analysis concepts such as Failure Mode, Effects and Criticality Analysis (FMECA), Fault Tree Analysis ( FTA ...Analysis (LORA) Condition Based Maintenance + (CBM+) Fault Tree Analysis ( FTA ) Failure Mode, Effects, and Criticality Analysis (FMECA) Maintenance Task...Reporting and Corrective Action System (FRACAS), Fault Tree Analysis ( FTA ), Level of Repair Analysis (LORA), Maintenance Task Analysis (MTA

Examining the Relationship Between Edaphic Variables and the Rooting System of Abies concolor in the southern Sierra Nevada

NASA Astrophysics Data System (ADS)

Wilson, A.; Jackson, R. B.; Tumber-Davila, S. J.

2017-12-01

An increase in the frequency and severity of droughts has been associated with the changing climate. These events have the potential to alter the composition and biogeography of forests, as well as increase tree mortality related to climate-induced stress. Already, an increase in tree mortality has been observed throughout the US. The recent drought in California led to millions of tree mortalities in the southern Sierra Nevada alone. In order to assess the potential impacts of these events on forest systems, it is imperative to understand what factors contribute to tree mortality. As plants become water-stressed, they may invest carbon more heavily belowground to reach a bigger pool of water, but their ability to adapt may be limited by the characteristics of the soil. In the Southern Sierra Critical Zone Observatory, a high tree mortality zone, we have selected both dead and living trees to examine the factors that contribute to root zone variability and belowground biomass investment by individual plants. A series of 15 cores surrounding the tree were taken to collect root and soil samples. These were then used to compare belowground rooting distributions with soil characteristics (texture, water holding capacity, pH, electric conductivity). Abies concolor is heavily affected by drought-induced mortality, therefore the rooting systems of dead Abies concolor trees were examined to determine the relationship between their rooting systems and environmental conditions. Examining the relationship between soil characteristics and rooting systems of trees may shed light on the plasticity of rooting systems and how trees adapt based on the characteristics of its environment. A better understanding of the factors that contribute to tree mortality can improve our ability to predict how forest systems may be impacted by climate-induced stress. Key words: Root systems, soil characteristics, drought, adaptation, terrestrial carbon, forest ecology

SILVA tree viewer: interactive web browsing of the SILVA phylogenetic guide trees.

PubMed

Beccati, Alan; Gerken, Jan; Quast, Christian; Yilmaz, Pelin; Glöckner, Frank Oliver

2017-09-30

Phylogenetic trees are an important tool to study the evolutionary relationships among organisms. The huge amount of available taxa poses difficulties in their interactive visualization. This hampers the interaction with the users to provide feedback for the further improvement of the taxonomic framework. The SILVA Tree Viewer is a web application designed for visualizing large phylogenetic trees without requiring the download of any software tool or data files. The SILVA Tree Viewer is based on Web Geographic Information Systems (Web-GIS) technology with a PostgreSQL backend. It enables zoom and pan functionalities similar to Google Maps. The SILVA Tree Viewer enables access to two phylogenetic (guide) trees provided by the SILVA database: the SSU Ref NR99 inferred from high-quality, full-length small subunit sequences, clustered at 99% sequence identity and the LSU Ref inferred from high-quality, full-length large subunit sequences. The Tree Viewer provides tree navigation, search and browse tools as well as an interactive feedback system to collect any kinds of requests ranging from taxonomy to data curation and improving the tool itself.

Tree Species Classification of Broadleaved Forests in Nagano, Central Japan, Using Airborne Laser Data and Multispectral Images

NASA Astrophysics Data System (ADS)

Deng, S.; Katoh, M.; Takenaka, Y.; Cheung, K.; Ishii, A.; Fujii, N.; Gao, T.

2017-10-01

This study attempted to classify three coniferous and ten broadleaved tree species by combining airborne laser scanning (ALS) data and multispectral images. The study area, located in Nagano, central Japan, is within the broadleaved forests of the Afan Woodland area. A total of 235 trees were surveyed in 2016, and we recorded the species, DBH, and tree height. The geographical position of each tree was collected using a Global Navigation Satellite System (GNSS) device. Tree crowns were manually detected using GNSS position data, field photographs, true-color orthoimages with three bands (red-green-blue, RGB), 3D point clouds, and a canopy height model derived from ALS data. Then a total of 69 features, including 27 image-based and 42 point-based features, were extracted from the RGB images and the ALS data to classify tree species. Finally, the detected tree crowns were classified into two classes for the first level (coniferous and broadleaved trees), four classes for the second level (Pinus densiflora, Larix kaempferi, Cryptomeria japonica, and broadleaved trees), and 13 classes for the third level (three coniferous and ten broadleaved species), using the 27 image-based features, 42 point-based features, all 69 features, and the best combination of features identified using a neighborhood component analysis algorithm, respectively. The overall classification accuracies reached 90 % at the first and second levels but less than 60 % at the third level. The classifications using the best combinations of features had higher accuracies than those using the image-based and point-based features and the combination of all of the 69 features.

High-resolution tree canopy mapping for New York City using LIDAR and object-based image analysis

NASA Astrophysics Data System (ADS)

MacFaden, Sean W.; O'Neil-Dunne, Jarlath P. M.; Royar, Anna R.; Lu, Jacqueline W. T.; Rundle, Andrew G.

2012-01-01

Urban tree canopy is widely believed to have myriad environmental, social, and human-health benefits, but a lack of precise canopy estimates has hindered quantification of these benefits in many municipalities. This problem was addressed for New York City using object-based image analysis (OBIA) to develop a comprehensive land-cover map, including tree canopy to the scale of individual trees. Mapping was performed using a rule-based expert system that relied primarily on high-resolution LIDAR, specifically its capacity for evaluating the height and texture of aboveground features. Multispectral imagery was also used, but shadowing and varying temporal conditions limited its utility. Contextual analysis was a key part of classification, distinguishing trees according to their physical and spectral properties as well as their relationships to adjacent, nonvegetated features. The automated product was extensively reviewed and edited via manual interpretation, and overall per-pixel accuracy of the final map was 96%. Although manual editing had only a marginal effect on accuracy despite requiring a majority of project effort, it maximized aesthetic quality and ensured the capture of small, isolated trees. Converting high-resolution LIDAR and imagery into usable information is a nontrivial exercise, requiring significant processing time and labor, but an expert system-based combination of OBIA and manual review was an effective method for fine-scale canopy mapping in a complex urban environment.

Greenhouse gas emissions and carbon sequestration by agroforestry systems in southeastern Brazil.

PubMed

Torres, Carlos Moreira Miquelino Eleto; Jacovine, Laércio Antônio Gonçalves; Nolasco de Olivera Neto, Sílvio; Fraisse, Clyde William; Soares, Carlos Pedro Boechat; de Castro Neto, Fernando; Ferreira, Lino Roberto; Zanuncio, José Cola; Lemes, Pedro Guilherme

2017-12-01

Agrosilvopastoral and silvopastoral systems can increase carbon sequestration, offset greenhouse gas (GHG) emissions and reduce the carbon footprint generated by animal production. The objective of this study was to estimate GHG emissions, the tree and grass aboveground biomass production and carbon storage in different agrosilvopastoral and silvopastoral systems in southeastern Brazil. The number of trees required to offset these emissions were also estimated. The GHG emissions were calculated based on pre-farm (e.g. agrochemical production, storage, and transportation), and on-farm activities (e.g. fertilization and machinery operation). Aboveground tree grass biomass and carbon storage in all systems was estimated with allometric equations. GHG emissions from the agroforestry systems ranged from 2.81 to 7.98 t CO 2 e ha -1 . Carbon storage in the aboveground trees and grass biomass were 54.6, 11.4, 25.7 and 5.9 t C ha -1 , and 3.3, 3.6, 3.8 and 3.3 t C ha -1 for systems 1, 2, 3 and 4, respectively. The number of trees necessary to offset the emissions ranged from 17 to 44 trees ha -1 , which was lower than the total planted in the systems. Agroforestry systems sequester CO 2 from the atmosphere and can help the GHG emission-reduction policy of the Brazilian government.

Reducing urban diffuse pollution and surface water flooding using retrofit street trees

NASA Astrophysics Data System (ADS)

Rothwell, James; Stringer, Pete; Causer, Katherine; Ryan, Matt; Mangan, Steve; Appleton, Ian; Savage, Mike

2016-04-01

Nature-based solutions for the management of urban stormwater have been growing in popularity, but there is a lack of empirical performance data for field-scale installations, especially in a UK context. To address this deficiency, a novel retrofit street tree demonstration project was commissioned in the City of Salford, near Manchester (UK). Three fifteen year-old London Plane trees were planted within a large roadside tree trench on an urban residential street. The DeepRoot Silvia Cell modular suspended pavement system was used to maximise soil volume, avoid compaction and support large tree growth. Road runoff is directed to the tree trench via AKO Slot Kerbs. Water is then distributed evenly throughout the whole system via a perforated pipe. Excess water is conveyed out of the system via an underdrain, which is subsequently connected to the sewer network. The tree trench is lined with an impermeable membrane. Access chambers are positioned on the inflow and outflow of the tree trench to facilitate hydrological and water quality monitoring. Installation was completed in autumn 2015 and monitoring will be conducted over a three year period. This paper will provide an overview of the installation process and present initial results on the pollutant removal performance and hydrological functioning of the system.

Interactive Tree Of Life v2: online annotation and display of phylogenetic trees made easy.

PubMed

Letunic, Ivica; Bork, Peer

2011-07-01

Interactive Tree Of Life (http://itol.embl.de) is a web-based tool for the display, manipulation and annotation of phylogenetic trees. It is freely available and open to everyone. In addition to classical tree viewer functions, iTOL offers many novel ways of annotating trees with various additional data. Current version introduces numerous new features and greatly expands the number of supported data set types. Trees can be interactively manipulated and edited. A free personal account system is available, providing management and sharing of trees in user defined workspaces and projects. Export to various bitmap and vector graphics formats is supported. Batch access interface is available for programmatic access or inclusion of interactive trees into other web services.

Canopy development of annual legumes and forage sorghum intercrops and its impact on forage yield

USDA-ARS?s Scientific Manuscript database

Livestock production is the most important agro-industry in many semiarid regions of the world including the Southern High Plains, USA. Declining water for irrigation requires novel technologies to sustain forage production necessary for livestock production. The objective of this study was to study...

N2 fixation of common and hairy vetches when intercropped into switchgrass

USDA-ARS?s Scientific Manuscript database

Interest in alternatives to synthetic nitrogen (N) fertilizer for switchgrass (Panicum virgatum L.) forage and bioenergy production continues to increase, and interseeding legumes into swards may be one such prospect. Common vetch (Vicia sativa L.) occurs naturally throughout the U.S. and has fewer ...

National Food Strategy: Kenya’s Approach to the Problem of Feeding the Nation

DTIC Science & Technology

1990-02-01

intercropping, agroforestry , preven- tion of soil erosion and rural afforestation. The new Arid and Semi Arid Lands Authority (ASAL) will establish irrigation...international organizations such as the International Council for Research in Agroforestry (ICRAF) has been beneficial. 13 To preserve Kenya’s forests, the

Effects of crop rotations and intercropping on soil health

USDA-ARS?s Scientific Manuscript database

Interest in evaluating the health of soil resources has been motivated by growing cognizance that soil is a critically important component of the earth’s biosphere, functioning not only in the production of food and fiber, but also in ecosystems services and global environmental quality. There was a...

Switchgrass Compositional Variations Arising from Spatial Distribution and Legume Intercropping

USDA-ARS?s Scientific Manuscript database

Switchgrass (Panicum virgatum) is a high–yielding, second-generation feedstock that can be grown on marginal land with minimal inputs. Due to the high genetic diversity within and among cultivars of this species, there may be a great amount of genotype x environment-induced differences among seconda...

Intercropping with switchgrass improves net greenhouse gas balance in hybrid poplar plantations on a sand soil

USDA-ARS?s Scientific Manuscript database

Highly productive, commercial hybrid poplar plantations are being managed in the Pacific Northwest for high-value timber production at relatively low stocking densities under irrigation. The open understory was used to produce switchgrass (Panicum virgatum) prior to canopy closure. The objectives ...

Simulation of Tsunami Resistance of a Pinus Thunbergii tree in Coastal Forest in Japan

NASA Astrophysics Data System (ADS)

Nanko, K.; Suzuki, S.; Noguchi, H.; Hagino, H.

2015-12-01

Forests reduce fluid force of tsunami, whereas extreme tsunami sometimes breaks down the forest trees. It is difficult to estimate the interactive relationship between the fluid and the trees because fluid deform tree architecture and deformed tree changes flow field. Dynamic tree deformation and fluid behavior should be clarified by fluid-structure interaction analysis. For the initial step, we have developed dynamic simulation of tree sway and breakage caused by tsunami based on a vibrating system with multiple degrees of freedom. The target specie of the simulation was Japanese black pine (pinus thunbergii), which is major specie in the coastal forest to secure livelihood area from the damage by blown sand and salt in Japanese coastal area. For the simulation, a tree was segmented into 0.2 m long circular truncated cones. Turning moment induced by tsunami and self-weight was calculated at each segment bottom. Tree deformation was computed on multi-degree-of-freedom vibration equation. Tree sway was simulated by iterative calculation of the tree deformation with time step 0.05 second with temporally varied flow velocity of tsunami. From the calculation of bending stress and turning moment at tree base, we estimated resistance of a Pinus thunbergii tree from tsunami against tree breakage.

Nearest Neighbor Searching in Binary Search Trees: Simulation of a Multiprocessor System.

ERIC Educational Resources Information Center

Stewart, Mark; Willett, Peter

1987-01-01

Describes the simulation of a nearest neighbor searching algorithm for document retrieval using a pool of microprocessors. Three techniques are described which allow parallel searching of a binary search tree as well as a PASCAL-based system, PASSIM, which can simulate these techniques. Fifty-six references are provided. (Author/LRW)

A Quality Classification System for Young Hardwood Trees - The First Step in Predicting Future Products

Treesearch

David L. Sonderman; Robert L. Brisbin

1978-01-01

Forest managers have no objective way to determine the relative value of culturally treated forest stands in terms of product potential. This paper describes the first step in the development of a quality classification system based on the measurement of individual tree characteristics for young hardwood stands.

Measuring soil and tree temperatures during prescribed fires with thermocouple probes

Treesearch

Stephen S. Sackett; Sally M. Haase

1992-01-01

Soil and cambium temperatures must be known to ascertain certain effects of prescribed fires on trees. Thermocouple-based systems were devised for measuring soil and cambium temperatures during prescribed fires. The systems, which incorporate both commercially available and custom components, perform three basic functions: data collection, data retrieval, and data...

Event Classification and Identification Based on the Characteristic Ellipsoid of Phasor Measurement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Jian; Diao, Ruisheng; Makarov, Yuri V.

2011-09-23

In this paper, a method to classify and identify power system events based on the characteristic ellipsoid of phasor measurement is presented. The decision tree technique is used to perform the event classification and identification. Event types, event locations and clearance times are identified by decision trees based on the indices of the characteristic ellipsoid. A sufficiently large number of transient events were simulated on the New England 10-machine 39-bus system based on different system configurations. Transient simulations taking into account different event types, clearance times and various locations are conducted to simulate phasor measurement. Bus voltage magnitudes and recordedmore » reactive and active power flows are used to build the characteristic ellipsoid. The volume, eccentricity, center and projection of the longest axis in the parameter space coordinates of the characteristic ellipsoids are used to classify and identify events. Results demonstrate that the characteristic ellipsoid and the decision tree are capable to detect the event type, location, and clearance time with very high accuracy.« less

Large-Scale Mixed Temperate Forest Mapping at the Single Tree Level using Airborne Laser Scanning

NASA Astrophysics Data System (ADS)

Scholl, V.; Morsdorf, F.; Ginzler, C.; Schaepman, M. E.

2017-12-01

Monitoring vegetation on a single tree level is critical to understand and model a variety of processes, functions, and changes in forest systems. Remote sensing technologies are increasingly utilized to complement and upscale the field-based measurements of forest inventories. Airborne laser scanning (ALS) systems provide valuable information in the vertical dimension for effective vegetation structure mapping. Although many algorithms exist to extract single tree segments from forest scans, they are often tuned to perform well in homogeneous coniferous or deciduous areas and are not successful in mixed forests. Other methods are too computationally expensive to apply operationally. The aim of this study was to develop a single tree detection workflow using leaf-off ALS data for the canton of Aargau in Switzerland. Aargau covers an area of over 1,400km2 and features mixed forests with various development stages and topography. Forest type was classified using random forests to guide local parameter selection. Canopy height model-based treetop maxima were detected and maintained based on the relationship between tree height and window size, used as a proxy to crown diameter. Watershed segmentation was used to generate crown polygons surrounding each maximum. The location, height, and crown dimensions of single trees were derived from the ALS returns within each polygon. Validation was performed through comparison with field measurements and extrapolated estimates from long-term monitoring plots of the Swiss National Forest Inventory within the framework of the Swiss Federal Institute for Forest, Snow, and Landscape Research. This method shows promise for robust, large-scale single tree detection in mixed forests. The single tree data will aid ecological studies as well as forest management practices. Figure description: Height-normalized ALS point cloud data (top) and resulting single tree segments (bottom) on the Laegeren mountain in Switzerland.

Implementation of a Goal-Based Systems Engineering Process Using the Systems Modeling Language (SysML)

NASA Technical Reports Server (NTRS)

Breckenridge, Jonathan T.; Johnson, Stephen B.

2013-01-01

This paper describes the core framework used to implement a Goal-Function Tree (GFT) based systems engineering process using the Systems Modeling Language. It defines a set of principles built upon by the theoretical approach described in the InfoTech 2013 ISHM paper titled "Goal-Function Tree Modeling for Systems Engineering and Fault Management" presented by Dr. Stephen B. Johnson. Using the SysML language, the principles in this paper describe the expansion of the SysML language as a baseline in order to: hierarchically describe a system, describe that system functionally within success space, and allocate detection mechanisms to success functions for system protection.

A universal hybrid decision tree classifier design for human activity classification.

PubMed

Chien, Chieh; Pottie, Gregory J

2012-01-01

A system that reliably classifies daily life activities can contribute to more effective and economical treatments for patients with chronic conditions or undergoing rehabilitative therapy. We propose a universal hybrid decision tree classifier for this purpose. The tree classifier can flexibly implement different decision rules at its internal nodes, and can be adapted from a population-based model when supplemented by training data for individuals. The system was tested using seven subjects each monitored by 14 triaxial accelerometers. Each subject performed fourteen different activities typical of daily life. Using leave-one-out cross validation, our decision tree produced average classification accuracies of 89.9%. In contrast, the MATLAB personalized tree classifiers using Gini's diversity index as the split criterion followed by optimally tuning the thresholds for each subject yielded 69.2%.

Diameter sensors for tree-length harvesting systems

Treesearch

T.P. McDonald; Robert B. Rummer; T.E. Grift

2003-01-01

Most cut-to-length (CTL) harvesters provide sensors for measuring diameter of trees as they are cut and processed. Among other uses, this capability provides a data collection tool for marketing of logs in real time. Logs can be sorted and stacked based on up-to-date market information, then transportation systems optimized to route wood to proper destinations at...

Development of a distributed air pollutant dry deposition modeling framework

Treesearch

Satoshi Hirabayashi; Charles N. Kroll; David J. Nowak

2012-01-01

A distributed air pollutant dry deposition modeling systemwas developed with a geographic information system (GIS) to enhance the functionality of i-Tree Eco (i-Tree, 2011). With the developed system, temperature, leaf area index (LAI) and air pollutant concentration in a spatially distributed form can be estimated, and based on these and other input variables, dry...

A novel knowledge-based system for interpreting complex engineering drawings: theory, representation, and implementation.

PubMed

Lu, Tong; Tai, Chiew-Lan; Yang, Huafei; Cai, Shijie

2009-08-01

We present a novel knowledge-based system to automatically convert real-life engineering drawings to content-oriented high-level descriptions. The proposed method essentially turns the complex interpretation process into two parts: knowledge representation and knowledge-based interpretation. We propose a new hierarchical descriptor-based knowledge representation method to organize the various types of engineering objects and their complex high-level relations. The descriptors are defined using an Extended Backus Naur Form (EBNF), facilitating modification and maintenance. When interpreting a set of related engineering drawings, the knowledge-based interpretation system first constructs an EBNF-tree from the knowledge representation file, then searches for potential engineering objects guided by a depth-first order of the nodes in the EBNF-tree. Experimental results and comparisons with other interpretation systems demonstrate that our knowledge-based system is accurate and robust for high-level interpretation of complex real-life engineering projects.

Reachability analysis of real-time systems using time Petri nets.

PubMed

Wang, J; Deng, Y; Xu, G

2000-01-01

Time Petri nets (TPNs) are a popular Petri net model for specification and verification of real-time systems. A fundamental and most widely applied method for analyzing Petri nets is reachability analysis. The existing technique for reachability analysis of TPNs, however, is not suitable for timing property verification because one cannot derive end-to-end delay in task execution, an important issue for time-critical systems, from the reachability tree constructed using the technique. In this paper, we present a new reachability based analysis technique for TPNs for timing property analysis and verification that effectively addresses the problem. Our technique is based on a concept called clock-stamped state class (CS-class). With the reachability tree generated based on CS-classes, we can directly compute the end-to-end time delay in task execution. Moreover, a CS-class can be uniquely mapped to a traditional state class based on which the conventional reachability tree is constructed. Therefore, our CS-class-based analysis technique is more general than the existing technique. We show how to apply this technique to timing property verification of the TPN model of a command and control (C2) system.

The Potential of GIS as a Management Tool for Avenue Trees Population in Small Communities; a Case Study of Idi-Shin Community, Ibadan, Nigeria

NASA Astrophysics Data System (ADS)

Olokeogun, O. S.; Akintola, O. O.; Abodunrin, E. K.

2016-06-01

This study demonstrates the potentials of Geographic Information System (GIS) as a management tool for avenue trees (Street trees) populations in small communities (using Idi-Ishin community, Ibadan, Nigeria as a case study). GIS is a decision support system which integrate data or set of data from different sources, bringing them under the same referencing system in a computer system. An Ikonos Imagery (1m Spatial Resolution) of the study area was digitized to produce a digital map using ArcGIS 10.1 version. The avenue trees species ≥ 5cm diameter at breast height (DBH) was selected for enumeration. These trees were then measured and tagged. The Height, Girth and Geographic location (X &Y coordinate) of the trees were measured with Haga altimeter, Girthing tape and Hand held Global Positioning System (GPS) respectively. The species and families of the trees enumerated were also identified. Data were analysed for basal area (BA) and volume (V). A total number of 43 avenue trees were assessed in Idi-Ishin Community. Roystonea regia accounted for the majority of the avenue trees (25.58%), followed by Polyanthia longiflora (23.26%), Gliricida seprium (20.93%), Eucalyptus toreliana (13.95%), Delunix regea (6.98%). However Terminalia catapa, Terminalia radii, Azadrachita indica and Newbodia levis had the same abundance of 2.33%. It was also observed that the benefits derived from these avenue trees includes; Carbon sequestration, Beautification, Wind break and shade. A spatial relational database was created for the assessed avenue trees using ArcCatalog of ArcGIS 10.1 version. Based on the findings from the study (which serves as baseline information for the management of the avenue trees in the study area), it was therefore recommended that subsequent assessment should be carried out at 3-5 year interval in other to ensure proper and continuous monitoring and updating of the data.

Investigation of Tree Spectral Reflectance Characteristics Using a Mobile Terrestrial Line Spectrometer and Laser Scanner

PubMed Central

Lin, Yi; Puttonen, Eetu; Hyyppä, Juha

2013-01-01

In mobile terrestrial hyperspectral imaging, individual trees often present large variations in spectral reflectance that may impact the relevant applications, but the related studies have been seldom reported. To fill this gap, this study was dedicated to investigating the spectral reflectance characteristics of individual trees with a Sensei mobile mapping system, which comprises a Specim line spectrometer and an Ibeo Lux laser scanner. The addition of the latter unit facilitates recording the structural characteristics of the target trees synchronously, and this is beneficial for revealing the characteristics of the spatial distributions of tree spectral reflectance with variations at different levels. Then, the parts of trees with relatively low-level variations can be extracted. At the same time, since it is difficult to manipulate the whole spectrum, the traditional concept of vegetation indices (VI) based on some particular spectral bands was taken into account here. Whether the assumed VIs capable of behaving consistently for the whole crown of each tree was also checked. The specific analyses were deployed based on four deciduous tree species and six kinds of VIs. The test showed that with the help of the laser scanner data, the parts of individual trees with relatively low-level variations can be located. Based on these parts, the relatively stable spectral reflectance characteristics for different tree species can be learnt. PMID:23877127

Agronomic aspects of strip intercropping lettuce with alyssum for biological control of aphids

USDA-ARS?s Scientific Manuscript database

Organic growers in California typically devote 5 to 10% of the area in lettuce (Lactuca sativa L.) fields to insectary strips of alyssum (Lobularia maritime (L.) Desv.) to attract syrphid flies (Syrphidae) whose larvae provide biological control of aphids. A 2-year study with organic romaine lettuc...

Row width influences wheat yield, but has little effect on wheat quality

USDA-ARS?s Scientific Manuscript database

Growers are interested in wide-row wheat production due to reductions in equipment inventory (lack of grain drill) and to allow intercropping of soybean into wheat. A trial was established during the 2012-2013 and 2013-2014 growing seasons in Wayne County and Wood County, Ohio to evaluate the effec...

Estimating demand for perennial pigeon pea in Malawi using choice experiments.

PubMed

Waldman, Kurt B; Ortega, David L; Richardson, Robert B; Snapp, Sieglinde S

2017-01-01

Perennial crops have numerous ecological and agronomic advantages over their annual counterparts. We estimate discrete choice models to evaluate farmers' preferences for perennial attributes of pigeon pea intercropped with maize in central and southern Malawi. Pigeon pea is a nitrogen-fixing leguminous crop, which has the potential to ameliorate soil fertility problems related to continuous maize cultivation, which are common in Southern Africa. Adoption of annual pigeon pea is relatively low but perennial production of pigeon pea may be more appealing to farmers due to some of the ancillary benefits associated with perenniality. We model perennial production of pigeon pea as a function of the attributes that differ between annual and perennial production: lower labor and seed requirements resulting from a single planting with multiple harvests, enhanced soil fertility and higher levels of biomass production. The primary tradeoff associated with perennial pigeon pea intercropped with maize is competition with maize in subsequent years of production. While maize yield is approximately twice as valuable to farmers as pigeon pea yield, we find positive yet heterogeneous demand for perenniality driven by soil fertility improvements and pigeon pea grain yield.

Soft error evaluation and vulnerability analysis in Xilinx Zynq-7010 system-on chip

NASA Astrophysics Data System (ADS)

Du, Xuecheng; He, Chaohui; Liu, Shuhuan; Zhang, Yao; Li, Yonghong; Xiong, Ceng; Tan, Pengkang

2016-09-01

Radiation-induced soft errors are an increasingly important threat to the reliability of modern electronic systems. In order to evaluate system-on chip's reliability and soft error, the fault tree analysis method was used in this work. The system fault tree was constructed based on Xilinx Zynq-7010 All Programmable SoC. Moreover, the soft error rates of different components in Zynq-7010 SoC were tested by americium-241 alpha radiation source. Furthermore, some parameters that used to evaluate the system's reliability and safety were calculated using Isograph Reliability Workbench 11.0, such as failure rate, unavailability and mean time to failure (MTTF). According to fault tree analysis for system-on chip, the critical blocks and system reliability were evaluated through the qualitative and quantitative analysis.

Manned space flight nuclear system safety. Volume 3: Reactor system preliminary nuclear safety analysis. Part 2A: Accident model document, appendix

NASA Technical Reports Server (NTRS)

1972-01-01

The detailed abort sequence trees for the reference zirconium hydride (ZrH) reactor power module that have been generated for each phase of the reference Space Base program mission are presented. The trees are graphical representations of causal sequences. Each tree begins with the phase identification and the dichotomy between success and failure. The success branch shows the mission phase objective as being achieved. The failure branch is subdivided, as conditions require, into various primary initiating abort conditions.

Object-based class modelling for multi-scale riparian forest habitat mapping

NASA Astrophysics Data System (ADS)

Strasser, Thomas; Lang, Stefan

2015-05-01

Object-based class modelling allows for mapping complex, hierarchical habitat systems. The riparian zone, including forests, represents such a complex ecosystem. Forests within riparian zones are biologically high productive and characterized by a rich biodiversity; thus considered of high community interest with an imperative to be protected and regularly monitored. Satellite earth observation (EO) provides tools for capturing the current state of forest habitats such as forest composition including intermixture of non-native tree species. Here we present a semi-automated object based image analysis (OBIA) approach for the mapping of riparian forests by applying class modelling of habitats based on the European Nature Information System (EUNIS) habitat classifications and the European Habitats Directive (HabDir) Annex 1. A very high resolution (VHR) WorldView-2 satellite image provided the required spatial and spectral details for a multi-scale image segmentation and rule-base composition to generate a six-level hierarchical representation of riparian forest habitats. Thereby habitats were hierarchically represented within an image object hierarchy as forest stands, stands of homogenous tree species and single trees represented by sunlit tree crowns. 522 EUNIS level 3 (EUNIS-3) habitat patches with a mean patch size (MPS) of 12,349.64 m2 were modelled from 938 forest stand patches (MPS = 6868.20 m2) and 43,742 tree stand patches (MPS = 140.79 m2). The delineation quality of the modelled EUNIS-3 habitats (focal level) was quantitatively assessed to an expert-based visual interpretation showing a mean deviation of 11.71%.

A diagnosis system using object-oriented fault tree models

NASA Technical Reports Server (NTRS)

Iverson, David L.; Patterson-Hine, F. A.

1990-01-01

Spaceborne computing systems must provide reliable, continuous operation for extended periods. Due to weight, power, and volume constraints, these systems must manage resources very effectively. A fault diagnosis algorithm is described which enables fast and flexible diagnoses in the dynamic distributed computing environments planned for future space missions. The algorithm uses a knowledge base that is easily changed and updated to reflect current system status. Augmented fault trees represented in an object-oriented form provide deep system knowledge that is easy to access and revise as a system changes. Given such a fault tree, a set of failure events that have occurred, and a set of failure events that have not occurred, this diagnosis system uses forward and backward chaining to propagate causal and temporal information about other failure events in the system being diagnosed. Once the system has established temporal and causal constraints, it reasons backward from heuristically selected failure events to find a set of basic failure events which are a likely cause of the occurrence of the top failure event in the fault tree. The diagnosis system has been implemented in common LISP using Flavors.

Method and system for dynamic probabilistic risk assessment

NASA Technical Reports Server (NTRS)

Dugan, Joanne Bechta (Inventor); Xu, Hong (Inventor)

2013-01-01

The DEFT methodology, system and computer readable medium extends the applicability of the PRA (Probabilistic Risk Assessment) methodology to computer-based systems, by allowing DFT (Dynamic Fault Tree) nodes as pivot nodes in the Event Tree (ET) model. DEFT includes a mathematical model and solution algorithm, supports all common PRA analysis functions and cutsets. Additional capabilities enabled by the DFT include modularization, phased mission analysis, sequence dependencies, and imperfect coverage.

Low-field nuclear magnetic resonance for the in vivo study of water content in trees

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoder, Jacob, E-mail: jlyoder@lanl.gov; Malone, Michael W.; Espy, Michelle A.

2014-09-15

Nuclear magnetic resonance (NMR) and magnetic resonance imaging have long been used to study water content in plants. Approaches have been primarily based on systems using large magnetic fields (∼1 T) to obtain NMR signals with good signal-to-noise. This is because the NMR signal scales approximately with the magnetic field strength squared. However, there are also limits to this approach in terms of realistic physiological configuration or those imposed by the size and cost of the magnet. Here we have taken a different approach – keeping the magnetic field low to produce a very light and inexpensive system, suitable formore » bulk water measurements on trees less than 5 cm in diameter, which could easily be duplicated to measure on many trees or from multiple parts of the same tree. Using this system we have shown sensitivity to water content in trees and their cuttings and observed a diurnal signal variation in tree water content in a greenhouse. We also demonstrate that, with calibration and modeling of the thermal polarization, the system is reliable under significant temperature variation.« less

Improving ensemble decision tree performance using Adaboost and Bagging

NASA Astrophysics Data System (ADS)

Hasan, Md. Rajib; Siraj, Fadzilah; Sainin, Mohd Shamrie

2015-12-01

Ensemble classifier systems are considered as one of the most promising in medical data classification and the performance of deceision tree classifier can be increased by the ensemble method as it is proven to be better than single classifiers. However, in a ensemble settings the performance depends on the selection of suitable base classifier. This research employed two prominent esemble s namely Adaboost and Bagging with base classifiers such as Random Forest, Random Tree, j48, j48grafts and Logistic Model Regression (LMT) that have been selected independently. The empirical study shows that the performance varries when different base classifiers are selected and even some places overfitting issue also been noted. The evidence shows that ensemble decision tree classfiers using Adaboost and Bagging improves the performance of selected medical data sets.

Knowledge, attitudes and practices in tamarind (Tamarindus indica L) use and conservation in Eastern Uganda.

PubMed

Ebifa-Othieno, Esther; Mugisha, Antony; Nyeko, Philip; Kabasa, John David

2017-01-21

Tamarindus indica L is one of the indigenous fruit tree species that traditionally contributes to food security and ecosystem stability in sub-Saharan Africa. We hypothesized that the indigenous people of Eastern Uganda have used T. indica for generations and developed practices that promote its conservation and therefore we expected that they possess an elaborate indigenous knowledge (IK) system and that most of them have planted the species. The aim of this study was to assess the influence of IK, attitudes and practices on the use and conservation of T. indica. A cross sectional survey was conducted in two districts purposively selected from the T. indica natural range. Focus group discussions, key informant interviews, semi-structured interviews and observation were used to collect data. Data was processed using qualitative analytical methods. Tamarindus indica was highly valued by the majority of the population. Tamarindus indica was used for food, medicinal, cultural, social, environmental amelioration and income generation purposes. The population possessed a high level of IK about T. indica evidenced by 18 categories of uses and multiple modes of use. Fruit pulp was the most commonly used tamarind product. Relative frequency of citation of the different uses provides insight into usage levels and IK possessed. The communities' food and medicinal uses concurred with scientific reports of health benefits of consuming T. indica. Approximately half of respondents had T. indica on their compounds or homegardens (53%). Fifty two percent of the tamarind population was self-propagated, 45% were planted while the propagation history for the remaining 3% was not known. Constraints towards planting T. indica included limited land, long maturation period and low monetary value. Fifty three percent of those who were growing T. indica did not carry out any silvicultural practices. The majority of T. indica encountered (87%) was intercropped with other crops or trees. Several beliefs and taboos regarding T. indica persist. Tamarindus indica has a high use value in the study area evidenced by multiple uses. Indigenous knowledge and uses concurred with scientifically proven nutritional and medicinal attributes of T. indica in literature which is significant given current trends towards affordable functional foods. The high level of IK has not translated into high rates of planting T. indica. There is need to encourage value-addition so as to maximize T. indica benefits and enhance conservation.

Creating ensembles of decision trees through sampling

DOEpatents

Kamath, Chandrika; Cantu-Paz, Erick

2005-08-30

A system for decision tree ensembles that includes a module to read the data, a module to sort the data, a module to evaluate a potential split of the data according to some criterion using a random sample of the data, a module to split the data, and a module to combine multiple decision trees in ensembles. The decision tree method is based on statistical sampling techniques and includes the steps of reading the data; sorting the data; evaluating a potential split according to some criterion using a random sample of the data, splitting the data, and combining multiple decision trees in ensembles.

Effect of silage from ryegrass intercropped with winter or common vetch for grazing dairy cows in small-scale dairy systems in Mexico.

PubMed

Hernández-Ortega, Martha; Heredia-Nava, Darwin; Espinoza-Ortega, Angelica; Sánchez-Vera, Ernesto; Arriaga-Jordán, Carlos M

2011-06-01

The objective was to determine the effect of including silages of annual ryegrass (Lolium multiflorum) intercropped with winter vetch (Vicia villosa) (ARG-VV) or with common vetch (Vicia sativa) (ARG-VS) compared with maize silage (MS) on milk yield and milk composition of dairy cows grazing cultivated perennial ryegrass-white clover pastures with supplemented concentrate during the dry season. Six Holstein dairy cows with a mean yield of 19.0 kg/cow/day at the beginning of the experiment were randomly assigned to a 3 × 3 repeated Latin square. Treatments were: 8 h/day intensive grazing, 3.6 kg of dry matter (DM) per cow per day of concentrate plus MS, and ARG-VV or ARG-VS ad libitum at a stocking rate of 3.0 cows/ha for three experimental periods of 3 weeks each. Milk yield (MY) and milk composition, live weight and body condition score as well as silage and concentrate intakes were recorded during the third week of each experimental period, and pasture intake was estimated indirectly from utilised metabolisable energy. Economic analysis was obtained by preparing partial budgets. There were no statistical differences (P > 0.10) in MY, milk fat or protein content nor for live weight, but there was significant difference (P < 0.10) in body condition score. There were non-statistical differences in silage DM intake (P < 0.11); however, significant differences (P < 0.10) were obtained for estimated grazed herbage intake whilst no differences for total DM intake. Slightly higher economic returns (10%) were obtained with ARG-VS over MS, and this was 7% higher than ARG-VV. It is concluded that ARG-VS could be an option for complementing grazing for small-scale dairy production systems in the dry season as it is comparable to MS in animal performance and slightly better in economic terms.

Linking definitions, mechanisms, and modeling of drought-induced tree death.

PubMed

Anderegg, William R L; Berry, Joseph A; Field, Christopher B

2012-12-01

Tree death from drought and heat stress is a critical and uncertain component in forest ecosystem responses to a changing climate. Recent research has illuminated how tree mortality is a complex cascade of changes involving interconnected plant systems over multiple timescales. Explicit consideration of the definitions, dynamics, and temporal and biological scales of tree mortality research can guide experimental and modeling approaches. In this review, we draw on the medical literature concerning human death to propose a water resource-based approach to tree mortality that considers the tree as a complex organism with a distinct growth strategy. This approach provides insight into mortality mechanisms at the tree and landscape scales and presents promising avenues into modeling tree death from drought and temperature stress. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of downed trees on harvesting productivity and costs in beetle-killed stands

Treesearch

Yaejun Kim; Woodam Chung; Hee Han; Nathaniel M. Anderson

2017-01-01

The mountain pine beetle (Dendroctonus ponderosae) has affected millions of acres of forests in the Rocky Mountain region in the United States. This study quantified the difficulty of harvesting beetle-killed stands caused by downed trees. A detailed time study was conducted on a whole-tree clearcut harvest using a ground-based system in western Montana in August 2015...

2005 AG20/20 Annual Review

NASA Technical Reports Server (NTRS)

Ross, Kenton W.; McKellip, Rodney D.

2005-01-01

Topics covered include: Implementation and Validation of Sensor-Based Site-Specific Crop Management; Enhanced Management of Agricultural Perennial Systems (EMAPS) Using GIS and Remote Sensing; Validation and Application of Geospatial Information for Early Identification of Stress in Wheat; Adapting and Validating Precision Technologies for Cotton Production in the Mid-Southern United States - 2004 Progress Report; Development of a System to Automatically Geo-Rectify Images; Economics of Precision Agriculture Technologies in Cotton Production-AG 2020 Prescription Farming Automation Algorithms; Field Testing a Sensor-Based Applicator for Nitrogen and Phosphorus Application; Early Detection of Citrus Diseases Using Machine Vision and DGPS; Remote Sensing of Citrus Tree Stress Levels and Factors; Spectral-based Nitrogen Sensing for Citrus; Characterization of Tree Canopies; In-field Sensing of Shallow Water Tables and Hydromorphic Soils with an Electromagnetic Induction Profiler; Maintaining the Competitiveness of Tree Fruit Production Through Precision Agriculture; Modeling and Visualizing Terrain and Remote Sensing Data for Research and Education in Precision Agriculture; Thematic Soil Mapping and Crop-Based Strategies for Site-Specific Management; and Crop-Based Strategies for Site-Specific Management.

Place-Based Education and Geographic Information Systems: Enhancing the Spatial Awareness of Middle School Students in Maine

ERIC Educational Resources Information Center

Perkins, Nancy; Hazelton, Eric; Erickson, Jeryl; Allan, Walter

2010-01-01

Spatial literacy is a new frontier in K-12 education. This article describes a place-based introductory GIS/GPS middle school curriculum unit in which students used measuring tools, GPS units, and My World GIS software to collect physical and spatial data of trees to create a schoolyard tree inventory. Maine students completed "memory…

Soil greenhouse gas (GHG) emissions from smallholder crop-livestock systems in Central Kenya

NASA Astrophysics Data System (ADS)

Ortiz Gonzalo, Daniel; Vaast, Philippe; de Neergaard, Andreas; Oelofse, Myles; Albrecht, Alain; Rosenstock, Todd S.

2017-04-01

Few studies measured empirically greenhouse gas (GHG) emissions in sub-Saharan Africa. More specifically, there is no experimental data on GHG emissions from coffee systems in East Africa and estimations with GHG calculators have shown some limitations. The objectives of our study are to: 1) Quantify soil GHG fluxes in smallholder coffee-dairy farms in Central Kenya and; 2) Compare results with the GHG emissions estimated with GHG calculators. The study area is situated in Murang'a County at 1700 m.a.s.l. on the Eastern slopes of the Aberdares Range, where coffee (Coffee arabica) is cultivated within integrated crop-livestock-agroforestry systems. We carried out GHG measurements along two cropping seasons using non-flow through non-steady static chambers. Sixty rectangular frames (0.355m x 0.255m) were installed at two representative farms, including the three main cropping systems found in the area: 1) Coffee (Coffee arabica); 2) Napier grass (Pennisetum purpureum); 3) Maize intercropped with beans (Zea mays and Phaseolus vulgaris). We used the gas pooling technique to overcome spatial variability and obtain a composite sample from the two treatment chambers: fertilized and non-fertilized. The sampling was performed twice per week during the rainy season and once per week during the dry season. Fertilizer and manure applications were followed by daily measurements during seven days after application. Annual fluxes (cumulative) in coffee plots ranged from 0.8 to 2.1 kg N2O-N ha-1, 6.3 to 8.2 Mg CO2-C ha-1 and -1.3 to -0.8 kg CH4-C ha-1, with higher fluxes during the rainy seasons. Emissions of N2O and CO2 from coffee plots were 20 to 80% higher than those in maize and napier grass. We found significant higher emissions in fertilized hot-spots (45 -190 % higher around coffee bushes perimeter, within maize rows and in napier holes) than in non-fertilized locations (between trees, between rows and between holes). Though this aspect is crucial for upscaling the emissions to farm scale, it is not always accounted in empirical models. GHG calculators overestimated both background and induced soil N2O emissions from fertilizer and manure applications in the three cropping systems. Our study contributes to the generation of underlying data and emission factors (EFs) for quantifying GHG emissions in tropical farming systems.

Does soil C accrual under perennial grasses managed for bioenergy offset fertilizer induced N2O emission?

USDA-ARS?s Scientific Manuscript database

Perennial grasses (e.g., switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerdardii Vitman) are often touted as being low input and as having a C-neutral foot print, but managing them as bioenergy feedstock means adding nitrogenous fertilizer or inter-cropping with legumes, which can i...

Water quality effects of switchgrass intercropping on pine forest in Coastal North Carolina.

Treesearch

Augustine Muwamba; Devendra Amatya; George M Chescheir; Jamie Nettles; Timothy Appelboom; Herbert Ssegane; Ernest Tollner; Mohamed Youssef; Francois Birgand; R. Wayne Skaggs; Shiying Tian

2017-01-01

Interplanting a cellulosic bioenergy crop (switchgrass, Panicum virgatum L.) between loblolly pine (Pinus taeda L.) rows could potentially provide a sustainable source of bio-feedstock without competing for land currently in food production. The objectives of this study were to: (1) quantify the concentrations and loads of drainage water nitrogen (N) and phosphorus (...

Sleeping site selection by agile gibbons: the influence of tree stability, fruit availability and predation risk.

PubMed

Cheyne, Susan M; Höing, Andrea; Rinear, John; Sheeran, Lori K

2012-01-01

Primates spend a significant proportion of their lives at sleeping sites: the selection of a secure and stable sleeping tree can be crucial for individual survival and fitness. We measured key characteristics of all tree species in which agile gibbons slept, including exposure of the tree crown, root system, height, species and presence of food. Gibbons most frequently slept in Dipterocarpaceae and Fabaceae trees and preferentially chose trees taller than average, slept above the mean canopy height and showed a preference for liana-free trees. These choices could reflect avoidance of competition with other frugivores, but we argue these choices reflect gibbons prioritizing avoidance of predation. The results highlight that gibbons are actively selecting and rejecting sleeping trees based on several characteristics. The importance of the presence of large trees for food is noted and provides insight into gibbon antipredatory behaviour. Copyright © 2013 S. Karger AG, Basel.

f-treeGC: a questionnaire-based family tree-creation software for genetic counseling and genome cohort studies.

PubMed

Tokutomi, Tomoharu; Fukushima, Akimune; Yamamoto, Kayono; Bansho, Yasushi; Hachiya, Tsuyoshi; Shimizu, Atsushi

2017-07-14

The Tohoku Medical Megabank project aims to create a next-generation personalized healthcare system by conducting large-scale genome-cohort studies involving three generations of local residents in the areas affected by the Great East Japan Earthquake. We collected medical and genomic information for developing a biobank to be used for this healthcare system. We designed a questionnaire-based pedigree-creation software program named "f-treeGC," which enables even less experienced medical practitioners to accurately and rapidly collect family health history and create pedigree charts. f-treeGC may be run on Adobe AIR. Pedigree charts are created in the following manner: 1) At system startup, the client is prompted to provide required information on the presence or absence of children; f-treeGC is capable of creating a pedigree up to three generations. 2) An interviewer fills out a multiple-choice questionnaire on genealogical information. 3) The information requested includes name, age, gender, general status, infertility status, pregnancy status, fetal status, and physical features or health conditions of individuals over three generations. In addition, information regarding the client and the proband, and birth order information, including multiple gestation, custody, multiple individuals, donor or surrogate, adoption, and consanguinity may be included. 4) f-treeGC shows only marriages between first cousins via the overlay function. 5) f-treeGC automatically creates a pedigree chart, and the chart-creation process is visible for inspection on the screen in real time. 6) The genealogical data may be saved as a file in the original format. The created/modified date and time may be changed as required, and the file may be password-protected and/or saved in read-only format. To enable sorting or searching from the database, the file name automatically contains the terms typed into the entry fields, including physical features or health conditions, by default. 7) Alternatively, family histories are collected using a completed foldable interview paper sheet named "f-sheet", which is identical to the questionnaire in f-treeGC. We developed a questionnaire-based family tree-creation software, named f-treeGC, which is fully compliant with international recommendations for standardized human pedigree nomenclature. The present software simplifies the process of collecting family histories and pedigrees, and has a variety of uses, from genome cohort studies or primary care to genetic counseling.

Dynamic replanning of 3D automated reconstruction using situation graph trees and illumination adjustment

NASA Astrophysics Data System (ADS)

Kohler, Sophie; Far, Aïcha Beya; Hirsch, Ernest

2007-01-01

This paper presents an original approach for the optimal 3D reconstruction of manufactured workpieces based on a priori planification of the task, enhanced on-line through dynamic adjustment of the lighting conditions, and built around a cognitive intelligent sensory system using so-called Situation Graph Trees. The system takes explicitely structural knowledge related to image acquisition conditions, type of illumination sources, contents of the scene (e. g., CAD models and tolerance information), etc. into account. The principle of the approach relies on two steps. First, a socalled initialization phase, leading to the a priori task plan, collects this structural knowledge. This knowledge is conveniently encoded, as a sub-part, in the Situation Graph Tree building the backbone of the planning system specifying exhaustively the behavior of the application. Second, the image is iteratively evaluated under the control of this Situation Graph Tree. The information describing the quality of the piece to analyze is thus extracted and further exploited for, e. g., inspection tasks. Lastly, the approach enables dynamic adjustment of the Situation Graph Tree, enabling the system to adjust itself to the actual application run-time conditions, thus providing the system with a self-learning capability.

Phosphorus acquisition and utilisation in crop legumes under global change.

PubMed

Pang, Jiayin; Ryan, Megan H; Lambers, Hans; Siddique, Kadambot Hm

2018-05-28

Improving phosphorus (P)-use efficiency in legumes is a worldwide challenge in the face of an increasing world population, dwindling global rock phosphate reserves, the relatively high P demand of legumes and global change. This review focuses on P acquisition of crop legumes in response to climate change. We advocate further studies on: firstly, the response of carboxylate exudation, mycorrhizas and root morphology to climate change and their role in P acquisition as dependent on edaphic factors; secondly, developing intercropping systems with a combination of a legume and another crop species to enhance P acquisition; and thirdly, the impact of the interactions of the major climate change factors on P acquisition in the field. Copyright © 2018 Elsevier Ltd. All rights reserved.

Agro-ecosystem and socio-economic role of homegarden agroforestry in Jabithenan District, North-Western Ethiopia: implication for climate change adaptation.

PubMed

Linger, Ewuketu

2014-01-01

Homegarden agroforestry is believed to be more diverse and provide multiple services for household than other monocropping system and this is due to the combination of crops, trees and livestock. The aim of this study was to assess socio-economic and agro-ecological role of homegardens in Jabithenan district, North-western Ethiopia. Two sites purposively and two villages randomly from each site were selected. Totally 96 households; in which 48 from homegarden agroforestry user and 48 from non-tree based garden user were selected for this study. Socio-economic data and potential economic and agro-ecosystem role of homegarden agroforestry over non-tree based garden were collected by using semi-structured and structured questionnaires to the households. Homegarden agroforestry significantly (P < 0.05) improved the farmers cash income than non-tree based garden. With insignificant garden size; homegarden agroforestry practice provides good socio-economical and agro-ecological service for farmers which have a higher implication for climate change adaptation than non-tree based garden.

Assessing School Readiness for a Practice Arrangement Using Decision Tree Methodology.

ERIC Educational Resources Information Center

Barger, Sara E.

1998-01-01

Questions in a decision-tree address mission, faculty interest, administrative support, and practice plan as a way of assessing arrangements for nursing faculty's clinical practice. Decisions should be based on congruence between the human resource allocation and the reward systems. (SK)

Investigating the performance of LiDAR-derived biomass information in hydromechanic slope stability modelling

NASA Astrophysics Data System (ADS)

Schmaltz, Elmar; Steger, Stefan; Bogaard, Thom; Van Beek, Rens; Glade, Thomas

2017-04-01

Hydromechanic slope stability models are often used to assess the landslide susceptibility of hillslopes. Some of these models are able to account for vegetation related effects when assessing slope stability. However, spatial information of required vegetation parameters (especially of woodland) that are defined by land cover type, tree species and stand density are mostly underrepresented compared to hydropedological and geomechanical parameters. The aim of this study is to assess how LiDAR-derived biomass information can help to distinguish distinct tree stand-immanent properties (e.g. stand density and diversity) and further improve the performance of hydromechanic slope stability models. We used spatial vegetation data produced from sophisticated algorithms that are able to separate single trees within a stand based on LiDAR point clouds and thus allow an extraordinary detailed determination of the aboveground biomass. Further, this information is used to estimate the species- and stand-related distribution of the subsurface biomass using an innovative approach to approximate root system architecture and development. The hydrological tree-soil interactions and their impact on the geotechnical stability of the soil mantle are then reproduced in the dynamic and spatially distributed slope stability model STARWARS/PROBSTAB. This study highlights first advances in the approximation of biomechanical reinforcement potential of tree root systems in tree stands. Based on our findings, we address the advantages and limitations of highly detailed biomass information in hydromechanic modelling and physically based slope failure prediction.

[Construction of information management-based virtual forest landscape and its application].

PubMed

Chen, Chongcheng; Tang, Liyu; Quan, Bing; Li, Jianwei; Shi, Song

2005-11-01

Based on the analysis of the contents and technical characteristics of different scale forest visualization modeling, this paper brought forward the principles and technical systems of constructing an information management-based virtual forest landscape. With the combination of process modeling and tree geometric structure description, a software method of interactively and parameterized tree modeling was developed, and the corresponding renderings and geometrical elements simplification algorithms were delineated to speed up rendering run-timely. As a pilot study, the geometrical model bases associated with the typical tree categories in Zhangpu County of Fujian Province, southeast China were established as template files. A Virtual Forest Management System prototype was developed with GIS component (ArcObject), OpenGL graphics environment, and Visual C++ language, based on forest inventory and remote sensing data. The prototype could be used for roaming between 2D and 3D, information query and analysis, and virtual and interactive forest growth simulation, and its reality and accuracy could meet the needs of forest resource management. Some typical interfaces of the system and the illustrative scene cross-sections of simulated masson pine growth under conditions of competition and thinning were listed.

Water-Tree Modelling and Detection for Underground Cables

NASA Astrophysics Data System (ADS)

Chen, Qi

In recent years, aging infrastructure has become a major concern for the power industry. Since its inception in early 20th century, the electrical system has been the cornerstone of an industrial society. Stable and uninterrupted delivery of electrical power is now a base necessity for the modern world. As the times march-on, however, the electrical infrastructure ages and there is the inevitable need to renew and replace the existing system. Unfortunately, due to time and financial constraints, many electrical systems today are forced to operate beyond their original design and power utilities must find ways to prolong the lifespan of older equipment. Thus, the concept of preventative maintenance arises. Preventative maintenance allows old equipment to operate longer and at better efficiency, but in order to implement preventative maintenance, the operators must know minute details of the electrical system, especially some of the harder to assess issues such water-tree. Water-tree induced insulation degradation is a problem typically associated with older cable systems. It is a very high impedance phenomenon and it is difficult to detect using traditional methods such as Tan-Delta or Partial Discharge. The proposed dissertation studies water-tree development in underground cables, potential methods to detect water-tree location and water-tree severity estimation. The dissertation begins by developing mathematical models of water-tree using finite element analysis. The method focuses on surface-originated vented tree, the most prominent type of water-tree fault in the field. Using the standard operation parameters of North American electrical systems, the water-tree boundary conditions are defined. By applying finite element analysis technique, the complex water-tree structure is broken down to homogeneous components. The result is a generalized representation of water-tree capacitance at different stages of development. The result from the finite element analysis is used to model water-tree in large system. Both empirical measurements and the mathematical model show that the impedance of early-stage water-tree is extremely large. As the result, traditional detection methods such Tan-Delta or Partial Discharge are not effective due to the excessively high accuracy requirement. A high-frequency pulse detection method is developed instead. The water-tree impedance is capacitive in nature and it can be reduced to manageable level by high-frequency inputs. The method is able to determine the location of early-stage water-tree in long-distance cables using economically feasible equipment. A pattern recognition method is developed to estimate the severity of water-tree using its pulse response from the high-frequency test method. The early-warning system for water-tree appearance is a tool developed to assist the practical implementation of the high-frequency pulse detection method. Although the equipment used by the detection method is economically feasible, it is still a specialized test and not designed for constant monitoring of the system. The test also place heavy stress on the cable and it is most effective when the cable is taken offline. As the result, utilities need a method to estimate the likelihood of water-tree presence before subjecting the cable to the specialized test. The early-warning system takes advantage of naturally occurring high-frequency events in the system and uses a deviation-comparison method to estimate the probability of water-tree presence on the cable. If the likelihood is high, then the utility can use the high-frequency pulse detection method to obtain accurate results. Specific pulse response patterns can be used to calculate the capacitance of water-tree. The calculated result, however, is subjected to margins of error due to limitations from the real system. There are both long-term and short-term methods to improve the accuracy. Computation algorithm improvement allows immediate improvement on accuracy of the capacitance estimation. The probability distribution of the calculation solution showed that improvements in waveform time-step measurement allow fundamental improves to the overall result.

Model authoring system for fail safe analysis

NASA Technical Reports Server (NTRS)

Sikora, Scott E.

1990-01-01

The Model Authoring System is a prototype software application for generating fault tree analyses and failure mode and effects analyses for circuit designs. Utilizing established artificial intelligence and expert system techniques, the circuits are modeled as a frame-based knowledge base in an expert system shell, which allows the use of object oriented programming and an inference engine. The behavior of the circuit is then captured through IF-THEN rules, which then are searched to generate either a graphical fault tree analysis or failure modes and effects analysis. Sophisticated authoring techniques allow the circuit to be easily modeled, permit its behavior to be quickly defined, and provide abstraction features to deal with complexity.

Pigeon Pea and Cowpea-Based Cropping Systems Improve Vesicular Arbuscular Mycorrhizal Fungal Colonisation of Subsequent Maize on the Alfisols in Central Malawi

PubMed Central

Semu, Ernest; Mrema, Jerome P.; Nalivata, Patson C.

2017-01-01

Mycorrhizal associations contribute to the sustainability of crop production systems through their roles in nutrient cycling and other benefits in the soil-plant ecosystems. A two-year study was conducted on the Alfisols of Lilongwe and Dowa districts, Central Malawi, to assess the vesicular-arbuscular mycorrhizal (VAM) fungal colonisation levels in pigeon pea, cowpea, and maize grown in sole cropping, legume-cereal, and legume-legume intercropping systems and in the maize grown in short rotation (year 2) as influenced by the previous cropping systems and N fertilizer application. The gridline intersect method was used to assess the VAM fungal colonisation levels. Results showed that all treatments that included legumes whether grown as sole crop, in legume-cereal or in legume-legume cropping systems in the previous year, had significantly higher (P < 0.05) VAM fungal colonisation of the rotational maize crop roots by a range 39% to 50% and 19% to 47% than those in maize supplied and not supplied with N fertilizer, respectively, in a maize-maize short rotation, at the Lilongwe site. A similar trend was reported for the Dowa site. Furthermore, there were positive correlations between VAM fungal colonisation and the plant P content, dry matter yield, and nodule numbers. Further studies may help to assess the diversity of VAM fungal species in Malawi soils and identify more adaptive ones for inoculation studies. PMID:28584528

Pigeon Pea and Cowpea-Based Cropping Systems Improve Vesicular Arbuscular Mycorrhizal Fungal Colonisation of Subsequent Maize on the Alfisols in Central Malawi.

PubMed

Njira, Keston O W; Semu, Ernest; Mrema, Jerome P; Nalivata, Patson C

2017-01-01

Mycorrhizal associations contribute to the sustainability of crop production systems through their roles in nutrient cycling and other benefits in the soil-plant ecosystems. A two-year study was conducted on the Alfisols of Lilongwe and Dowa districts, Central Malawi, to assess the vesicular-arbuscular mycorrhizal (VAM) fungal colonisation levels in pigeon pea, cowpea, and maize grown in sole cropping, legume-cereal, and legume-legume intercropping systems and in the maize grown in short rotation (year 2) as influenced by the previous cropping systems and N fertilizer application. The gridline intersect method was used to assess the VAM fungal colonisation levels. Results showed that all treatments that included legumes whether grown as sole crop, in legume-cereal or in legume-legume cropping systems in the previous year, had significantly higher ( P < 0.05) VAM fungal colonisation of the rotational maize crop roots by a range 39% to 50% and 19% to 47% than those in maize supplied and not supplied with N fertilizer, respectively, in a maize-maize short rotation, at the Lilongwe site. A similar trend was reported for the Dowa site. Furthermore, there were positive correlations between VAM fungal colonisation and the plant P content, dry matter yield, and nodule numbers. Further studies may help to assess the diversity of VAM fungal species in Malawi soils and identify more adaptive ones for inoculation studies.

Effect of shade on Arabica coffee berry disease development: Toward an agroforestry system to reduce disease impact.

PubMed

Mouen Bedimo, J A; Njiayouom, I; Bieysse, D; Ndoumbè Nkeng, M; Cilas, C; Nottéghem, J L

2008-12-01

Coffee berry disease (CBD), caused by Colletotrichum kahawae, is a major constraint for Arabica coffee cultivation in Africa. The disease is specific to green berries and can lead to 60% harvest losses. In Cameroon, mixed cropping systems of coffee with other crops, such as fruit trees, are very widespread agricultural practices. Fruit trees are commonly planted at random on coffee farms, providing a heterogeneous shading pattern for coffee trees growing underneath. Based on a recent study of CBD, it is known that those plants can reduce disease incidence. To assess the specific effect of shade, in situ and in vitro disease development was compared between coffee trees shaded artificially by a net and trees located in full sunlight. In the field, assessments confirmed a reduction in CBD on trees grown under shade compared with those grown in full sunlight. Artificial inoculations in the laboratory showed that shade did not have any effect on the intrinsic susceptibility of coffee berries to CBD. Coffee shading mainly acts on environmental parameters in limiting disease incidence. In addition to reducing yield losses, agroforestry system may also be helpful in reducing chemical control of the disease and in diversifying coffee growers' incomes.

A resource-saving collective approach to biomedical semantic role labeling

PubMed Central

2014-01-01

Background Biomedical semantic role labeling (BioSRL) is a natural language processing technique that identifies the semantic roles of the words or phrases in sentences describing biological processes and expresses them as predicate-argument structures (PAS’s). Currently, a major problem of BioSRL is that most systems label every node in a full parse tree independently; however, some nodes always exhibit dependency. In general SRL, collective approaches based on the Markov logic network (MLN) model have been successful in dealing with this problem. However, in BioSRL such an approach has not been attempted because it would require more training data to recognize the more specialized and diverse terms found in biomedical literature, increasing training time and computational complexity. Results We first constructed a collective BioSRL system based on MLN. This system, called collective BIOSMILE (CBIOSMILE), is trained on the BioProp corpus. To reduce the resources used in BioSRL training, we employ a tree-pruning filter to remove unlikely nodes from the parse tree and four argument candidate identifiers to retain candidate nodes in the tree. Nodes not recognized by any candidate identifier are discarded. The pruned annotated parse trees are used to train a resource-saving MLN-based system, which is referred to as resource-saving collective BIOSMILE (RCBIOSMILE). Our experimental results show that our proposed CBIOSMILE system outperforms BIOSMILE, which is the top BioSRL system. Furthermore, our proposed RCBIOSMILE maintains the same level of accuracy as CBIOSMILE using 92% less memory and 57% less training time. Conclusions This greatly improved efficiency makes RCBIOSMILE potentially suitable for training on much larger BioSRL corpora over more biomedical domains. Compared to real-world biomedical corpora, BioProp is relatively small, containing only 445 MEDLINE abstracts and 30 event triggers. It is not large enough for practical applications, such as pathway construction. We consider it of primary importance to pursue SRL training on large corpora in the future. PMID:24884358

Response-based selection of barley cultivars and legume species for complementarity: Root morphology and exudation in relation to nutrient source.

PubMed

Giles, Courtney D; Brown, Lawrie K; Adu, Michael O; Mezeli, Malika M; Sandral, Graeme A; Simpson, Richard J; Wendler, Renate; Shand, Charles A; Menezes-Blackburn, Daniel; Darch, Tegan; Stutter, Marc I; Lumsdon, David G; Zhang, Hao; Blackwell, Martin S A; Wearing, Catherine; Cooper, Patricia; Haygarth, Philip M; George, Timothy S

2017-02-01

Phosphorus (P) and nitrogen (N) use efficiency may be improved through increased biodiversity in agroecosystems. Phenotypic variation in plants' response to nutrient deficiency may influence positive complementarity in intercropping systems. A multicomponent screening approach was used to assess the influence of P supply and N source on the phenotypic plasticity of nutrient foraging traits in barley (H. vulgare L.) and legume species. Root morphology and exudation were determined in six plant nutrient treatments. A clear divergence in the response of barley and legumes to the nutrient treatments was observed. Root morphology varied most among legumes, whereas exudate citrate and phytase activity were most variable in barley. Changes in root morphology were minimized in plants provided with ammonium in comparison to nitrate but increased under P deficiency. Exudate phytase activity and pH varied with legume species, whereas citrate efflux, specific root length, and root diameter lengths were more variable among barley cultivars. Three legume species and four barley cultivars were identified as the most responsive to P deficiency and the most contrasting of the cultivars and species tested. Phenotypic response to nutrient availability may be a promising approach for the selection of plant combinations for minimal input cropping systems. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Diversified Native Species Restoration for Recovery of Multiple Ecosystem Services in a Highly Disturbed Tropical Dry Forest Landscape of Southwestern Nicaragua

NASA Astrophysics Data System (ADS)

Williams-Guillen, K.; Otterstrom, S.; Perla, C.

2015-12-01

Tropical dry forests have been reduced to a fraction of their original extent in the Neotropics due to conversion to agriculture and cattle pasture. While TDF can recover via natural regeneration, resulting forests are dominated by wind-dispersed pioneer species of limited value for frugivorous wildlife. Additionally, passive restoration can be perceived as "abandonment" resulting in neighbors casually invading property to rear livestock and extract timber. In 2007, the NGO Paso Pacífico initiated restoration in a highly degraded tropical dry forest landscape of southwestern Nicaragua; funded by an ex-ante carbon purchase, the project was designed to integrate multiple native tree species known to provide resources used by local wildlife. We restored roughly 400 hectares spanning a rainfall gradient from dry to transitional moist forest, using reforestation (planting 70 species of tree seedlings in degraded pastures on a 4x4 m grid, leaving occurring saplings) and assisted regeneration (clearing vines and competing vegetation from saplings in natural regeneration and strategically managing canopy cover). In just over seven years, mean carbon increased nearly threefold, from to 21.5±5.0 to 57.9±9.6 SE tonnes/ha. Current carbon stocks match those of 20-year-old forests in the area, accumulated in less than a decade. Stem density per 15-m radius plot decreased from 16.3±2.3 to 12.5±0.9 SE, while species richness increased from 3.9±0.4 to 18.4±1.4 SE. Alpha richness of woody stems across plots increased from 36 to 94 species, and over 20 tree species established as a result of natural dispersal and recruitment. We have observed sensitive species such as spider monkeys and parrots foraging in restoration areas. Managed reforestation is a highly effective method for rapidly restoring the functionality of multiple ecosystem services in degraded TDF, particularly when social and political realities force restoration to coexist with human productive activities. Project techniques were developed in collaboration with local community members and incorporated indigenous practices regarding lunar cycles, intercropping, and other management aspects. We suggest that this integration was a critical aspect to project success, and that these approaches could be widely adapted throughout Central America.

HT/HP x-tree and downhole fiber optic connectors and their use on subsea intelligent wells

NASA Astrophysics Data System (ADS)

Wright, Perry; Barlow, Stewart

2004-12-01

Offshore Oil and Gas R&D has been committed to improved reservoir performance through production monitoring. Technology improvements in these areas offer the greatest potential returns through increased knowledge of the reservoir, and the improvements in real-time production control that the technology and knowledge base can provide. One area of technology that supports this development is the growing application of fiber optic sensors for reservoir and production monitoring. These sensors cannot function in isolation, and need support in the form of fiber optic connection systems for x-tree penetrations. ODI have been developing products for fiber optic tree penetrations and down-hole wet connections for the last 4 years, working with Intelligent Wells Group at BP America Production Company in Houston. This paper discusses the application and reliability of fiber optic connectors, and reviews the development of the ODI I-CONN connection system and its application for vertical and horizontal x-trees, work-over systems and running tools, and down-hole systems.

A framework for incorporating the effects of hydrodynamic stresses on forest photosynthesis and evaporation

NASA Astrophysics Data System (ADS)

Matheny, A. M.; Bohrer, G.; Thompsen, J.; Frasson, R.; Frasson, C. D.; Ivanov, V. Y.

2012-12-01

Hydraulic limitations are known to control transpiration in forest ecosystems when the soil is drying or when the vapor pressure deficit between the air and stomata (VPD) is very large, but they can also impact stomatal apertures under conditions of adequate soil moisture and lower evaporative demand. We use the NACP flux measurements and models dataset for multiple site/model intercomparisons to evaluate the degree to which currently un-resolved high-frequency (sub-daily) hydrodynamic stresses affect the error in model prediction of latent heat flux. We find that many site-model combinations are characterized by a typical pattern of overestimation of afternoon flux and a corresponding underestimation of pre-noon flux. We hypothesize that this pattern is a result of un-resolved afternoon stomata closure due to hydrodynamic stresses. In a forest plot at the University of Michigan Biological Station, we use measurements of leaf-level stomata conductance and water potential to demonstrate that trees of similar type - mid-late successional deciduous trees - have very different hydrodynamic strategies that lead to differences in their temporal patterns of stomata conductance. We found that red oak trees continue transpiring despite a large stem-water deficit while red maple trees regulate stomata to maintain a high water potential. Red oaks, which are ring porous, are also able to access more soil water, assumingly from deeper ground layers and have higher conductivity, compared with the maples, which are diffuse porous. These differences will lead to large differences in stomata conductance and water use based on the species composition of the forest. We also demonstrate that the size and shape of the tree stem-branch system may lead to differences in the extent of hydrodynamic stress, which may change the forest respiration patterns as the forest grows and ages. We propose a framework to resolve tree hydrodynamics in global and regional models. It is based on the Finite-Elements Tree-Crown Hydrodynamics model (FETCH) combined with a statistical functional-type/hydraulic-type/size representation of the trees in the forest. Lidar and multi-spectral images of the forest can be used to obtain numerical distributions of species and size of individual tree crowns needed to initialize such simulations. FETCH simulates water flow through the tree as a simplified system of porous media conduits. It explicitly resolves spatiotemporal hydraulic stresses throughout the tree's hydraulic system that cannot be easily represented using other stomatal-conductance models. It uses a physical representation of water flow in a 3-D tree-stem-branch system assuming the xylem is a porous media. Empirical equations relate water potential at the branch-tips to stomata conductance at leaves connected to these branches. FETCH calculates the hydrodynamic stress related closure of stomata, provided the atmospheric and biological variables from the global model, and could replace the current empirical formulation for stomata adjustment based on soil moisture.

A conceptual approach to approximate tree root architecture in infinite slope models

NASA Astrophysics Data System (ADS)

Schmaltz, Elmar; Glade, Thomas

2016-04-01

Vegetation-related properties - particularly tree root distribution and coherent hydrologic and mechanical effects on the underlying soil mantle - are commonly not considered in infinite slope models. Indeed, from a geotechnical point of view, these effects appear to be difficult to be reproduced reliably in a physically-based modelling approach. The growth of a tree and the expansion of its root architecture are directly connected with both intrinsic properties such as species and age, and extrinsic factors like topography, availability of nutrients, climate and soil type. These parameters control four main issues of the tree root architecture: 1) Type of rooting; 2) maximum growing distance to the tree stem (radius r); 3) maximum growing depth (height h); and 4) potential deformation of the root system. Geometric solids are able to approximate the distribution of a tree root system. The objective of this paper is to investigate whether it is possible to implement root systems and the connected hydrological and mechanical attributes sufficiently in a 3-dimensional slope stability model. Hereby, a spatio-dynamic vegetation module should cope with the demands of performance, computation time and significance. However, in this presentation, we focus only on the distribution of roots. The assumption is that the horizontal root distribution around a tree stem on a 2-dimensional plane can be described by a circle with the stem located at the centroid and a distinct radius r that is dependent on age and species. We classified three main types of tree root systems and reproduced the species-age-related root distribution with three respective mathematical solids in a synthetic 3-dimensional hillslope ambience. Thus, two solids in an Euclidian space were distinguished to represent the three root systems: i) cylinders with radius r and height h, whilst the dimension of latter defines the shape of a taproot-system or a shallow-root-system respectively; ii) elliptic paraboloids represent a cordate-root-system with radius r, height h and a constant, species-independent curvature. This procedure simplifies the classification of tree species into the three defined geometric solids. In this study we introduce a conceptual approach to estimate the 2- and 3-dimensional distribution of different tree root systems, and to implement it in a raster environment, as it is used in infinite slope models. Hereto we used the PCRaster extension in a python framework. The results show that root distribution and root growth are spatially reproducible in a simple raster framework. The outputs exhibit significant effects for a synthetically generated slope on local scale for equal time-steps. The preliminary results depict an initial step to develop a vegetation module that can be coupled with hydro-mechanical slope stability models. This approach is expected to yield a valuable contribution to the implementation of vegetation-related properties, in particular effects of root-reinforcement, into physically-based approaches using infinite slope models.

Tree root systems competing for soil moisture in a 3D soil–plant model

Treesearch

Gabriele Manoli; Sara Bonetti; Jean-Christophe Domec; Mario Putti; Gabriel Katul; Marco Marani

2014-01-01

Competition for water among multiple tree rooting systems is investigated using a soil–plant model that accounts for soil moisture dynamics and root water uptake (RWU), whole plant transpiration, and leaflevel photosynthesis. The model is based on a numerical solution to the 3D Richards equation modified to account for a 3D RWU, trunk xylem, and stomatal conductances....

Soil compaction associated with cut-to-length and whole-tree harvesting of a coniferous forest

Treesearch

Sang-Kyun Han; Han Han-Sup; Deborah Page-Dumroese; Leonard R. Johnson

2009-01-01

The degree and extent of soil compaction, which may reduce productivity of forest soils, is believed to vary by the type of harvesting system, and a field-based study was conducted to compare soil compaction from cut-to-length (CTL) and whole-tree (WT) harvesting operations. The CTL harvesting system used less area to transport logs to the landings than did the WT...

Developing Biomass Equations for Western Hemlock and Red Alder Trees in Western Oregon Forests

Treesearch

Krishna Poudel; Hailemariam Temesgen

2016-01-01

Biomass estimates are required for reporting carbon, assessing feedstock availability, and assessing forest fire threat. We developed diameter- and height-based biomass equations for Western hemlock (Tsuga heterophylla (Raf.) Sarg.) and red alder (Alnus rubra Bong.) trees in Western Oregon. A system of component biomass...

Impacts of switchgrass intercropping in traditional pine forests on hydrology and water quality in the southeastern United States.

Treesearch

Devendra Amatya; G.M. Chescheir; J.E. Nettles

2016-01-01

Preliminary results indicate that switchgrass (Panicum virgatum L.), grown as a cellulosic biofuel between managed loblolly pine (Pinus taeda L.) beds on the Atlantic Coastal Plain forests has no significant effect on shallow ground water table and stream outflows. Although management operations (e.g. harvesting, shearing between pine rows, raking, and bedding)...

Soil organic matter fractions in loblolly pine forests of Coastal North Carolina managed for bioenergy production

Treesearch

Kevan J. Minick; Brian D. Strahm; Thomas R. Fox; Eric B. Surce; Zakiya H. Leggett

2015-01-01

Dependence on foreign oil continues to increase, and concern over rising atmospheric CO2 and other greenhouse gases has intensified research into sustainable biofuel production. Intercropping switchgrass (Panicum virgatum L.) between planted rows of loblolly pine (Pinus taeda L.) offers an opportunity to utilize inter-row space that typically contains herbaceous and...

Automated identification and geometrical features extraction of individual trees from Mobile Laser Scanning data in Budapest

NASA Astrophysics Data System (ADS)

Koma, Zsófia; Székely, Balázs; Folly-Ritvay, Zoltán; Skobrák, Ferenc; Koenig, Kristina; Höfle, Bernhard

2016-04-01

Mobile Laser Scanning (MLS) is an evolving operational measurement technique for urban environment providing large amounts of high resolution information about trees, street features, pole-like objects on the street sides or near to motorways. In this study we investigate a robust segmentation method to extract the individual trees automatically in order to build an object-based tree database system. We focused on the large urban parks in Budapest (Margitsziget and Városliget; KARESZ project) which contained large diversity of different kind of tree species. The MLS data contained high density point cloud data with 1-8 cm mean absolute accuracy 80-100 meter distance from streets. The robust segmentation method contained following steps: The ground points are determined first. As a second step cylinders are fitted in vertical slice 1-1.5 meter relative height above ground, which is used to determine the potential location of each single trees trunk and cylinder-like object. Finally, residual values are calculated as deviation of each point from a vertically expanded fitted cylinder; these residual values are used to separate cylinder-like object from individual trees. After successful parameterization, the model parameters and the corresponding residual values of the fitted object are extracted and imported into the tree database. Additionally, geometric features are calculated for each segmented individual tree like crown base, crown width, crown length, diameter of trunk, volume of the individual trees. In case of incompletely scanned trees, the extraction of geometric features is based on fitted circles. The result of the study is a tree database containing detailed information about urban trees, which can be a valuable dataset for ecologist, city planners, planting and mapping purposes. Furthermore, the established database will be the initial point for classification trees into single species. MLS data used in this project had been measured in the framework of KARESZ project for whole Budapest. BSz contributed as an Alexander von Humboldt Research Fellow.

Computer aided diagnosis system for the Alzheimer's disease based on partial least squares and random forest SPECT image classification.

PubMed

Ramírez, J; Górriz, J M; Segovia, F; Chaves, R; Salas-Gonzalez, D; López, M; Alvarez, I; Padilla, P

2010-03-19

This letter shows a computer aided diagnosis (CAD) technique for the early detection of the Alzheimer's disease (AD) by means of single photon emission computed tomography (SPECT) image classification. The proposed method is based on partial least squares (PLS) regression model and a random forest (RF) predictor. The challenge of the curse of dimensionality is addressed by reducing the large dimensionality of the input data by downscaling the SPECT images and extracting score features using PLS. A RF predictor then forms an ensemble of classification and regression tree (CART)-like classifiers being its output determined by a majority vote of the trees in the forest. A baseline principal component analysis (PCA) system is also developed for reference. The experimental results show that the combined PLS-RF system yields a generalization error that converges to a limit when increasing the number of trees in the forest. Thus, the generalization error is reduced when using PLS and depends on the strength of the individual trees in the forest and the correlation between them. Moreover, PLS feature extraction is found to be more effective for extracting discriminative information from the data than PCA yielding peak sensitivity, specificity and accuracy values of 100%, 92.7%, and 96.9%, respectively. Moreover, the proposed CAD system outperformed several other recently developed AD CAD systems. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Model-Based Design of Tree WSNs for Decentralized Detection.

PubMed

Tantawy, Ashraf; Koutsoukos, Xenofon; Biswas, Gautam

2015-08-20

The classical decentralized detection problem of finding the optimal decision rules at the sensor and fusion center, as well as variants that introduce physical channel impairments have been studied extensively in the literature. The deployment of WSNs in decentralized detection applications brings new challenges to the field. Protocols for different communication layers have to be co-designed to optimize the detection performance. In this paper, we consider the communication network design problem for a tree WSN. We pursue a system-level approach where a complete model for the system is developed that captures the interactions between different layers, as well as different sensor quality measures. For network optimization, we propose a hierarchical optimization algorithm that lends itself to the tree structure, requiring only local network information. The proposed design approach shows superior performance over several contentionless and contention-based network design approaches.

The growth of the UniTree mass storage system at the NASA Center for Computational Sciences

NASA Technical Reports Server (NTRS)

Tarshish, Adina; Salmon, Ellen

1993-01-01

In October 1992, the NASA Center for Computational Sciences made its Convex-based UniTree system generally available to users. The ensuing months saw the growth of near-online data from nil to nearly three terabytes, a doubling of the number of CPU's on the facility's Cray YMP (the primary data source for UniTree), and the necessity for an aggressive regimen for repacking sparse tapes and hierarchical 'vaulting' of old files to freestanding tape. Connectivity was enhanced as well with the addition of UltraNet HiPPI. This paper describes the increasing demands placed on the storage system's performance and throughput that resulted from the significant augmentation of compute-server processor power and network speed.

Discriminant forest classification method and system

DOEpatents

Chen, Barry Y.; Hanley, William G.; Lemmond, Tracy D.; Hiller, Lawrence J.; Knapp, David A.; Mugge, Marshall J.

2012-11-06

A hybrid machine learning methodology and system for classification that combines classical random forest (RF) methodology with discriminant analysis (DA) techniques to provide enhanced classification capability. A DA technique which uses feature measurements of an object to predict its class membership, such as linear discriminant analysis (LDA) or Andersen-Bahadur linear discriminant technique (AB), is used to split the data at each node in each of its classification trees to train and grow the trees and the forest. When training is finished, a set of n DA-based decision trees of a discriminant forest is produced for use in predicting the classification of new samples of unknown class.

Simulation-Based Model Checking for Nondeterministic Systems and Rare Events

DTIC Science & Technology

2016-03-24

year, we have investigated AO* search and Monte Carlo Tree Search algorithms to complement and enhance CMU’s SMCMDP. 1 Final Report, March 14... tree , so we can use it to find the probability of reachability for a property in PRISM’s Probabilistic LTL. By finding the maximum probability of...savings, particularly when handling very large models. 2.3 Monte Carlo Tree Search The Monte Carlo sampling process in SMCMDP can take a long time to

Allelopathic activity and chemical constituents of walnut (Juglans regia) leaf litter in walnut-winter vegetable agroforestry system.

PubMed

Wang, Qian; Xu, Zheng; Hu, Tingxing; Rehman, Hafeez Ur; Chen, Hong; Li, Zhongbin; Ding, Bo; Hu, Hongling

2014-01-01

Walnut agroforestry systems have many ecological and economic benefits when intercropped with cool-season species. However, decomposing leaf litter is one of the main sources of allelochemicals in such systems. In this study, lettuce (Lactuca sativa var. angustata) was grown in the soil incorporated with walnut leaf litter to assess its allelopathic activity. Lettuce growth and physiological processes were inhibited by walnut leaf litter, especially during early growth stage (1-2 euphylla period) or with large amount of litter addition. The plants treated by small amount of leaf litter recovered their growth afterwards, while the inhibition for 180 g leaf litter persisted until harvest. Twenty-eight compounds were identified in the leaf litter, and several of them were reported to be phytotoxic, which may be responsible for the stress induced by walnut leaf litter. Thus, for highest economic value of vegetables such as lettuce, excessive incorporation of leaf litter should be discouraged.

Fuzzy tree automata and syntactic pattern recognition.

PubMed

Lee, E T

1982-04-01

An approach of representing patterns by trees and processing these trees by fuzzy tree automata is described. Fuzzy tree automata are defined and investigated. The results include that the class of fuzzy root-to-frontier recognizable ¿-trees is closed under intersection, union, and complementation. Thus, the class of fuzzy root-to-frontier recognizable ¿-trees forms a Boolean algebra. Fuzzy tree automata are applied to processing fuzzy tree representation of patterns based on syntactic pattern recognition. The grade of acceptance is defined and investigated. Quantitative measures of ``approximate isosceles triangle,'' ``approximate elongated isosceles triangle,'' ``approximate rectangle,'' and ``approximate cross'' are defined and used in the illustrative examples of this approach. By using these quantitative measures, a house, a house with high roof, and a church are also presented as illustrative examples. In addition, three fuzzy tree automata are constructed which have the capability of processing the fuzzy tree representations of ``fuzzy houses,'' ``houses with high roofs,'' and ``fuzzy churches,'' respectively. The results may have useful applications in pattern recognition, image processing, artificial intelligence, pattern database design and processing, image science, and pictorial information systems.

[Compatible biomass models of natural spruce (Picea asperata)].

PubMed

Wang, Jin Chi; Deng, Hua Feng; Huang, Guo Sheng; Wang, Xue Jun; Zhang, Lu

2017-10-01

By using nonlinear measurement error method, the compatible tree volume and above ground biomass equations were established based on the volume and biomass data of 150 sampling trees of natural spruce (Picea asperata). Two approaches, controlling directly under total aboveground biomass and controlling jointly from level to level, were used to design the compatible system for the total aboveground biomass and the biomass of four components (stem, bark, branch and foliage), and the total ground biomass could be estimated independently or estimated simultaneously in the system. The results showed that the R 2 of the one variable and bivariate compatible tree volume and aboveground biomass equations were all above 0.85, and the maximum value reached 0.99. The prediction effect of the volume equations could be improved significantly when tree height was included as predictor, while it was not significant in biomass estimation. For the compatible biomass systems, the one variable model based on controlling jointly from level to level was better than the model using controlling directly under total above ground biomass, but the bivariate models of the two methods were similar. Comparing the imitative effects of the one variable and bivariate compatible biomass models, the results showed that the increase of explainable variables could significantly improve the fitness of branch and foliage biomass, but had little effect on other components. Besides, there was almost no difference between the two methods of estimation based on the comparison.

All-optical conversion scheme from binary to its MTN form with the help of nonlinear material based tree-net architecture

NASA Astrophysics Data System (ADS)

Maiti, Anup Kumar; Nath Roy, Jitendra; Mukhopadhyay, Sourangshu

2007-08-01

In the field of optical computing and parallel information processing, several number systems have been used for different arithmetic and algebraic operations. Therefore an efficient conversion scheme from one number system to another is very important. Modified trinary number (MTN) has already taken a significant role towards carry and borrow free arithmetic operations. In this communication, we propose a tree-net architecture based all optical conversion scheme from binary number to its MTN form. Optical switch using nonlinear material (NLM) plays an important role.

A decision tree-based on-line preventive control strategy for power system transient instability prevention

NASA Astrophysics Data System (ADS)

Xu, Yan; Dong, Zhao Yang; Zhang, Rui; Wong, Kit Po

2014-02-01

Maintaining transient stability is a basic requirement for secure power system operations. Preventive control deals with modifying the system operating point to withstand probable contingencies. In this article, a decision tree (DT)-based on-line preventive control strategy is proposed for transient instability prevention of power systems. Given a stability database, a distance-based feature estimation algorithm is first applied to identify the critical generators, which are then used as features to develop a DT. By interpreting the splitting rules of DT, preventive control is realised by formulating the rules in a standard optimal power flow model and solving it. The proposed method is transparent in control mechanism, on-line computation compatible and convenient to deal with multi-contingency. The effectiveness and efficiency of the method has been verified on New England 10-machine 39-bus test system.

Dataset for forensic analysis of B-tree file system.

PubMed

Wani, Mohamad Ahtisham; Bhat, Wasim Ahmad

2018-06-01

Since B-tree file system (Btrfs) is set to become de facto standard file system on Linux (and Linux based) operating systems, Btrfs dataset for forensic analysis is of great interest and immense value to forensic community. This article presents a novel dataset for forensic analysis of Btrfs that was collected using a proposed data-recovery procedure. The dataset identifies various generalized and common file system layouts and operations, specific node-balancing mechanisms triggered, logical addresses of various data structures, on-disk records, recovered-data as directory entries and extent data from leaf and internal nodes, and percentage of data recovered.

The growth of the UniTree mass storage system at the NASA Center for Computational Sciences: Some lessons learned

NASA Technical Reports Server (NTRS)

Tarshish, Adina; Salmon, Ellen

1994-01-01

In October 1992, the NASA Center for Computational Sciences made its Convex-based UniTree system generally available to users. The ensuing months saw growth in every area. Within 26 months, data under UniTree control grew from nil to over 12 terabytes, nearly all of it stored on robotically mounted tape. HiPPI/UltraNet was added to enhance connectivity, and later HiPPI/TCP was added as well. Disks and robotic tape silos were added to those already under UniTree's control, and 18-track tapes were upgraded to 36-track. The primary data source for UniTree, the facility's Cray Y-MP/4-128, first doubled its processing power and then was replaced altogether by a C98/6-256 with nearly two-and-a-half times the Y-MP's combined peak gigaflops. The Convex/UniTree software was upgraded from version 1.5 to 1.7.5, and then to 1.7.6. Finally, the server itself, a Convex C3240, was upgraded to a C3830 with a second I/O bay, doubling the C3240's memory and capacity for I/O. This paper describes insights gained and reinforced with the burgeoning demands on the UniTree storage system and the significant increases in performance gained from the many upgrades.

Systematic Model-in-the-Loop Test of Embedded Control Systems

NASA Astrophysics Data System (ADS)

Krupp, Alexander; Müller, Wolfgang

Current model-based development processes offer new opportunities for verification automation, e.g., in automotive development. The duty of functional verification is the detection of design flaws. Current functional verification approaches exhibit a major gap between requirement definition and formal property definition, especially when analog signals are involved. Besides lack of methodical support for natural language formalization, there does not exist a standardized and accepted means for formal property definition as a target for verification planning. This article addresses several shortcomings of embedded system verification. An Enhanced Classification Tree Method is developed based on the established Classification Tree Method for Embeded Systems CTM/ES which applies a hardware verification language to define a verification environment.

Monitoring individual tree-based change with airborne lidar.

PubMed

Duncanson, Laura; Dubayah, Ralph

2018-05-01

Understanding the carbon flux of forests is critical for constraining the global carbon cycle and managing forests to mitigate climate change. Monitoring forest growth and mortality rates is critical to this effort, but has been limited in the past, with estimates relying primarily on field surveys. Advances in remote sensing enable the potential to monitor tree growth and mortality across landscapes. This work presents an approach to measure tree growth and loss using multidate lidar campaigns in a high-biomass forest in California, USA. Individual tree crowns were delineated in 2008 and again in 2013 using a 3D crown segmentation algorithm, with derived heights and crown radii extracted and used to estimate individual tree aboveground biomass. Tree growth, loss, and aboveground biomass were analyzed with respect to tree height and crown radius. Both tree growth and loss rates decrease with increasing tree height, following the expectation that trees slow in growth rate as they age. Additionally, our aboveground biomass analysis suggests that, while the system is a net source of aboveground carbon, these carbon dynamics are governed by size class with the largest sources coming from the loss of a relatively small number of large individuals. This study demonstrates that monitoring individual tree-based growth and loss can be conducted with multidate airborne lidar, but these methods remain relatively immature. Disparities between lidar acquisitions were particularly difficult to overcome and decreased the sample of trees analyzed for growth rate in this study to 21% of the full number of delineated crowns. However, this study illuminates the potential of airborne remote sensing for ecologically meaningful forest monitoring at an individual tree level. As methods continue to improve, airborne multidate lidar will enable a richer understanding of the drivers of tree growth, loss, and aboveground carbon flux.

Epiphytes in wooded pastures: Isolation matters for lichen but not for bryophyte species richness

PubMed Central

Keller, Christine; Scheidegger, Christoph; Bergamini, Ariel

2017-01-01

Sylvo-pastoral systems are species-rich man-made landscapes that are currently often severely threatened by abandonment or management intensification. At low tree densities, single trees in these systems represent habitat islands for epiphytic cryptogams. Here, we focused on sycamore maple (Acer pseudoplatanus) wooded pastures in the northern European Alps. We assessed per tree species richness of bryophytes and lichens on 90 sycamore maple trees distributed across six study sites. We analysed the effects of a range of explanatory variables (tree characteristics, environmental variables and isolation measures) on the richness of epiphytic bryophytes and lichens and various functional subgroups (based on diaspore size, habitat preference and red list status). Furthermore, we estimated the effect of these variables on the occurrence of two specific bryophyte species (Tayloria rudolphiana, Orthotrichum rogeri) and one lichen species (Lobaria pulmonaria) of major conservation concern. Bryophytes and lichens, as well as their subgroups, were differently and sometimes contrastingly affected by the variables considered: tree diameter at breast height had no significant effect on bryophytes but negatively affected many lichen groups; tree phenological age positively affected red-listed lichens but not red-listed bryophytes; increasing isolation from neighbouring trees negatively affected lichens but not bryophytes. However, the high-priority bryophyte species T. rudolphiana was also negatively affected by increased isolation at small spatial scales. Orthotrichum rogeri was more frequent on young trees and L. pulmonaria was more frequent on trees with thin stems and large crowns. The results indicate that local dispersal is important for lichens, whereas long distance dispersal seems to be more important for colonisation by bryophytes. Furthermore, our study highlights that different conservation measures need to be taken depending on the taxonomic and functional species group or the individual species that is addressed. In practice, for the conservation of a high overall richness in sylvo-pastoral systems, it is crucial to sustain not only old and large trees but rather a wide range of tree sizes and ages. PMID:28742881

Typology of Ohio, USA, Tree Farmers Based Upon Forestry Outreach Needs

NASA Astrophysics Data System (ADS)

Starr, SE; McConnell, TE; Bruskotter, JS; Williams, RA

2015-02-01

This study differentiated groups of Ohio tree farmers through multivariate clustering of their perceived needs for forest management outreach. Tree farmers were surveyed via a mailed questionnaire. Respondents were asked to rate, on a 1-7 scale, their informational needs for 26 outreach topics, which were reduced to six factors. Based on these factors, three clusters were identified—holistic managers, environmental stewards, and pragmatic tree farmers. Cluster assignment of individuals was dependent upon a tree farmer's age, acreage owned, and number of years enrolled in the American Tree Farm System. Holistic managers showed a greater interest in the outreach topics while pragmatic tree farmers displayed an overall lesser interest. Across clusters, print media and in-person workshops were preferred over emails and webinars for receiving forest management information. In-person workshops should be no more than 1 day events, held on a weekday, during the daytime, at a cost not exceeding 35. Programming related to environmental influences, which included managing for forest insects and diseases, was concluded to have the greater potential to impact clientele among all outreach factors due to the information being applicable across demographics and/or management objectives.

Genomics-assisted breeding in fruit trees.

PubMed

Iwata, Hiroyoshi; Minamikawa, Mai F; Kajiya-Kanegae, Hiromi; Ishimori, Motoyuki; Hayashi, Takeshi

2016-01-01

Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the plant to assess the marketable product (fruit). In this article, we describe the potential of genomics-assisted breeding, which uses these novel genomics-based approaches, to break through these barriers in conventional fruit tree breeding. We first introduce the molecular marker systems and whole-genome sequence data that are available for fruit tree breeding. Next we introduce the statistical methods for biparental linkage and quantitative trait locus (QTL) mapping as well as GWAS and GS. We then review QTL mapping, GWAS, and GS studies conducted on fruit trees. We also review novel technologies for rapid generation advancement. Finally, we note the future prospects of genomics-assisted fruit tree breeding and problems that need to be overcome in the breeding.

Genomics-assisted breeding in fruit trees

PubMed Central

Iwata, Hiroyoshi; Minamikawa, Mai F.; Kajiya-Kanegae, Hiromi; Ishimori, Motoyuki; Hayashi, Takeshi

2016-01-01

Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the plant to assess the marketable product (fruit). In this article, we describe the potential of genomics-assisted breeding, which uses these novel genomics-based approaches, to break through these barriers in conventional fruit tree breeding. We first introduce the molecular marker systems and whole-genome sequence data that are available for fruit tree breeding. Next we introduce the statistical methods for biparental linkage and quantitative trait locus (QTL) mapping as well as GWAS and GS. We then review QTL mapping, GWAS, and GS studies conducted on fruit trees. We also review novel technologies for rapid generation advancement. Finally, we note the future prospects of genomics-assisted fruit tree breeding and problems that need to be overcome in the breeding. PMID:27069395

Decision tree methods: applications for classification and prediction.

PubMed

Song, Yan-Yan; Lu, Ying

2015-04-25

Decision tree methodology is a commonly used data mining method for establishing classification systems based on multiple covariates or for developing prediction algorithms for a target variable. This method classifies a population into branch-like segments that construct an inverted tree with a root node, internal nodes, and leaf nodes. The algorithm is non-parametric and can efficiently deal with large, complicated datasets without imposing a complicated parametric structure. When the sample size is large enough, study data can be divided into training and validation datasets. Using the training dataset to build a decision tree model and a validation dataset to decide on the appropriate tree size needed to achieve the optimal final model. This paper introduces frequently used algorithms used to develop decision trees (including CART, C4.5, CHAID, and QUEST) and describes the SPSS and SAS programs that can be used to visualize tree structure.

A Fault Tree Approach to Needs Assessment -- An Overview.

ERIC Educational Resources Information Center

Stephens, Kent G.

A "failsafe" technology is presented based on a new unified theory of needs assessment. Basically the paper discusses fault tree analysis as a technique for enhancing the probability of success in any system by analyzing the most likely modes of failure that could occur and then suggesting high priority avoidance strategies for those…

Phase synchronization based on a Dual-Tree Complex Wavelet Transform

NASA Astrophysics Data System (ADS)

Ferreira, Maria Teodora; Domingues, Margarete Oliveira; Macau, Elbert E. N.

2016-11-01

In this work, we show the applicability of our Discrete Complex Wavelet Approach (DCWA) to verify the phenomenon of phase synchronization transition in two coupled chaotic Lorenz systems. DCWA is based on the phase assignment from complex wavelet coefficients obtained by using a Dual-Tree Complex Wavelet Transform (DT-CWT). We analyzed two coupled chaotic Lorenz systems, aiming to detect the transition from non-phase synchronization to phase synchronization. In addition, we check how good is the method in detecting periods of 2π phase-slips. In all experiments, DCWA is compared with classical phase detection methods such as the ones based on arctangent and Hilbert transform showing a much better performance.

Venous tree separation in the liver: graph partitioning using a non-ising model.

PubMed

O'Donnell, Thomas; Kaftan, Jens N; Schuh, Andreas; Tietjen, Christian; Soza, Grzegorz; Aach, Til

2011-01-01

Entangled tree-like vascular systems are commonly found in the body (e.g., in the peripheries and lungs). Separation of these systems in medical images may be formulated as a graph partitioning problem given an imperfect segmentation and specification of the tree roots. In this work, we show that the ubiquitous Ising-model approaches (e.g., Graph Cuts, Random Walker) are not appropriate for tackling this problem and propose a novel method based on recursive minimal paths for doing so. To motivate our method, we focus on the intertwined portal and hepatic venous systems in the liver. Separation of these systems is critical for liver intervention planning, in particular when resection is involved. We apply our method to 34 clinical datasets, each containing well over a hundred vessel branches, demonstrating its effectiveness.

A decision tree for differentiating multiple system atrophy from Parkinson's disease using 3-T MR imaging.

PubMed

Nair, Shalini Rajandran; Tan, Li Kuo; Mohd Ramli, Norlisah; Lim, Shen Yang; Rahmat, Kartini; Mohd Nor, Hazman

2013-06-01

To develop a decision tree based on standard magnetic resonance imaging (MRI) and diffusion tensor imaging to differentiate multiple system atrophy (MSA) from Parkinson's disease (PD). 3-T brain MRI and DTI (diffusion tensor imaging) were performed on 26 PD and 13 MSA patients. Regions of interest (ROIs) were the putamen, substantia nigra, pons, middle cerebellar peduncles (MCP) and cerebellum. Linear, volumetry and DTI (fractional anisotropy and mean diffusivity) were measured. A three-node decision tree was formulated, with design goals being 100 % specificity at node 1, 100 % sensitivity at node 2 and highest combined sensitivity and specificity at node 3. Nine parameters (mean width, fractional anisotropy (FA) and mean diffusivity (MD) of MCP; anteroposterior diameter of pons; cerebellar FA and volume; pons and mean putamen volume; mean FA substantia nigra compacta-rostral) showed statistically significant (P < 0.05) differences between MSA and PD with mean MCP width, anteroposterior diameter of pons and mean FA MCP chosen for the decision tree. Threshold values were 14.6 mm, 21.8 mm and 0.55, respectively. Overall performance of the decision tree was 92 % sensitivity, 96 % specificity, 92 % PPV and 96 % NPV. Twelve out of 13 MSA patients were accurately classified. Formation of the decision tree using these parameters was both descriptive and predictive in differentiating between MSA and PD. • Parkinson's disease and multiple system atrophy can be distinguished on MR imaging. • Combined conventional MRI and diffusion tensor imaging improves the accuracy of diagnosis. • A decision tree is descriptive and predictive in differentiating between clinical entities. • A decision tree can reliably differentiate Parkinson's disease from multiple system atrophy.

Tree cover in sub-Saharan Africa: rainfall and fire constrain forest and savanna as alternative stable states.

PubMed

Staver, A Carla; Archibald, Sally; Levin, Simon

2011-05-01

Savannas are known as ecosystems with tree cover below climate-defined equilibrium values. However, a predictive framework for understanding constraints on tree cover is lacking. We present (a) a spatially extensive analysis of tree cover and fire distribution in sub-Saharan Africa, and (b) a model, based on empirical results, demonstrating that savanna and forest may be alternative stable states in parts of Africa, with implications for understanding savanna distributions. Tree cover does not increase continuously with rainfall, but rather is constrained to low (<50%, "savanna") or high tree cover (>75%, "forest"). Intermediate tree cover rarely occurs. Fire, which prevents trees from establishing, differentiates high and low tree cover, especially in areas with rainfall between 1000 mm and 2000 mm. Fire is less important at low rainfall (<1000 mm), where rainfall limits tree cover, and at high rainfall (>2000 mm), where fire is rare. This pattern suggests that complex interactions between climate and disturbance produce emergent alternative states in tree cover. The relationship between tree cover and fire was incorporated into a dynamic model including grass, savanna tree saplings, and savanna trees. Only recruitment from sapling to adult tree varied depending on the amount of grass in the system. Based on our empirical analysis and previous work, fires spread only at tree cover of 40% or less, producing a sigmoidal fire probability distribution as a function of grass cover and therefore a sigmoidal sapling to tree recruitment function. This model demonstrates that, given relatively conservative and empirically supported assumptions about the establishment of trees in savannas, alternative stable states for the same set of environmental conditions (i.e., model parameters) are possible via a fire feedback mechanism. Integrating alternative stable state dynamics into models of biome distributions could improve our ability to predict changes in biome distributions and in carbon storage under climate and global change scenarios.

Optimisation of biomass productivity of black locust (Robinia pseudoacacia L.) on marginal lands - a case study in Lower Lusatia, NE Germany

NASA Astrophysics Data System (ADS)

Seserman, Diana-Maria; Veste, Maik; Freese, Dirk

2017-04-01

The profitability of reclaiming post-mining areas depends on the tree biomass productivity and the restoration of ecosystem functions, such as improving soil and water quality. Agroforestry systems, regarded as combined land-use systems of trees and crops, have the ability to facilitate soil development while reducing wind speed, soil erosion and evaporation. Achieving the maximum biomass productivity of the tree stands depends on the corresponding soil conditions and water availability, but is also influenced by stand structure and the competition between individual trees. For this purpose, black locust (Robinia pseudoacacia L.) trees were planted in a Nelder design in 2010, on a reclaimed post-mining site of the open-cast lignite mining in Welzow Süd (Brandenburg, Germany). Black locust is regarded as a drought-adapted tree species and commonly used for the reclamation of former lignite mining sites in Lower Lusatia, Germany. The Nelder design encompasses angles of arc of equal measure and with the same origin traversed by successive circumferences set at a predefined radial distance. Accordingly, a total of 1071 trees were planted in Welzow Süd at the intersection between 63 spokes and 17 circumferences and at densities ranging from 0.4 to 8.0 m2, with the aim of examining the influence of stand density on the tree growth in a timeframe of six years. In order to evaluate the biomass production of the trees and to determine an optimal planting density on a marginal land, various scenarios were assessed with the help of the Yield-SAFE model, a parameter-sparse process-based agroforestry model. The study revealed the consequences of choosing different tree densities on the tree biomass productivity and water use of trees in relation to the competition for light and water. References Keesman KJ, van der Werf W, van Keulen H, 2007. Production ecology of agroforestry systems: A minimal mechanistic model and analytical derivation of the land equivalent ratio. Mathematical Biosciences, vol. 209, pp. 608-623. Mantovani D, Veste M, Böhm C, Vignudelli M, Freese D, 2015. Drought impact on the spatial and temporal variation of growth performance and plant water status of black locust (Robinia pseudoacacia L.) in agroforestry systems in Lower Lusatia (Germany). iForest 8, 743-757. Mantovani D, Veste M, Freese D, 2014. Black locust (Robinia pseudoacacia L.) ecophysiological and morphological adaptations to drought and their consequence on biomass production and water use efficiency. New Zealand Journal of Forestry 44, 29. van der Werf W, Keesman K, Burgess PJ, Graves AR, Pilbeam D, Incoll LD, Metselaar K, Mayus M, Stappers R, van Keulen H, Palma JHN, Dupraz C, 2007. Yield-SAFE: a parameter-sparse process-based dynamic model for predicting resource capture, growth and production in agroforestry systems. Ecological Engineering, vol. 29, pp. 419-433.

A construction scheme of web page comment information extraction system based on frequent subtree mining

NASA Astrophysics Data System (ADS)

Zhang, Xiaowen; Chen, Bingfeng

2017-08-01

Based on the frequent sub-tree mining algorithm, this paper proposes a construction scheme of web page comment information extraction system based on frequent subtree mining, referred to as FSM system. The entire system architecture and the various modules to do a brief introduction, and then the core of the system to do a detailed description, and finally give the system prototype.

Model-Based Design of Tree WSNs for Decentralized Detection †

PubMed Central

Tantawy, Ashraf; Koutsoukos, Xenofon; Biswas, Gautam

2015-01-01

The classical decentralized detection problem of finding the optimal decision rules at the sensor and fusion center, as well as variants that introduce physical channel impairments have been studied extensively in the literature. The deployment of WSNs in decentralized detection applications brings new challenges to the field. Protocols for different communication layers have to be co-designed to optimize the detection performance. In this paper, we consider the communication network design problem for a tree WSN. We pursue a system-level approach where a complete model for the system is developed that captures the interactions between different layers, as well as different sensor quality measures. For network optimization, we propose a hierarchical optimization algorithm that lends itself to the tree structure, requiring only local network information. The proposed design approach shows superior performance over several contentionless and contention-based network design approaches. PMID:26307989

Evolving optimised decision rules for intrusion detection using particle swarm paradigm

NASA Astrophysics Data System (ADS)

Sivatha Sindhu, Siva S.; Geetha, S.; Kannan, A.

2012-12-01

The aim of this article is to construct a practical intrusion detection system (IDS) that properly analyses the statistics of network traffic pattern and classify them as normal or anomalous class. The objective of this article is to prove that the choice of effective network traffic features and a proficient machine-learning paradigm enhances the detection accuracy of IDS. In this article, a rule-based approach with a family of six decision tree classifiers, namely Decision Stump, C4.5, Naive Baye's Tree, Random Forest, Random Tree and Representative Tree model to perform the detection of anomalous network pattern is introduced. In particular, the proposed swarm optimisation-based approach selects instances that compose training set and optimised decision tree operate over this trained set producing classification rules with improved coverage, classification capability and generalisation ability. Experiment with the Knowledge Discovery and Data mining (KDD) data set which have information on traffic pattern, during normal and intrusive behaviour shows that the proposed algorithm produces optimised decision rules and outperforms other machine-learning algorithm.

Data Clustering and Evolving Fuzzy Decision Tree for Data Base Classification Problems

NASA Astrophysics Data System (ADS)

Chang, Pei-Chann; Fan, Chin-Yuan; Wang, Yen-Wen

Data base classification suffers from two well known difficulties, i.e., the high dimensionality and non-stationary variations within the large historic data. This paper presents a hybrid classification model by integrating a case based reasoning technique, a Fuzzy Decision Tree (FDT), and Genetic Algorithms (GA) to construct a decision-making system for data classification in various data base applications. The model is major based on the idea that the historic data base can be transformed into a smaller case-base together with a group of fuzzy decision rules. As a result, the model can be more accurately respond to the current data under classifying from the inductions by these smaller cases based fuzzy decision trees. Hit rate is applied as a performance measure and the effectiveness of our proposed model is demonstrated by experimentally compared with other approaches on different data base classification applications. The average hit rate of our proposed model is the highest among others.

Regulation of water flux through tropical forest canopy trees: do universal rules apply?

PubMed

Meinzer, F C; Goldstein, G; Andrade, J L

2001-01-01

Tropical moist forests are notable for their richness in tree species. The presence of such a diverse tree flora presents potential problems for scaling up estimates of water use from individual trees to entire stands and for drawing generalizations about physiological regulation of water use in tropical trees. We measured sapwood area or sap flow, or both, in 27 co-occurring canopy species in a Panamanian forest to determine the extent to which relationships between tree size, sapwood area and sap flow were species-specific, or whether they were constrained by universal functional relationships between tree size, conducting xylem area, and water use. For the 24 species in which active xylem area was estimated over a range of size classes, diameter at breast height (DBH) accounted for 98% of the variation in sapwood area and 67% of the variation in sapwood depth when data for all species were combined. The DBH alone also accounted for > or = 90% of the variation in both maximum and total daily sap flux density in the outermost 2 cm of sapwood for all species taken together. Maximum sap flux density measured near the base of the tree occurred at about 1,400 h in the largest trees and 1,130 h in the smallest trees studied, and DBH accounted for 93% of the variation in the time of day at which maximum sap flow occurred. The shared relationship between tree size and time of maximum sap flow at the base of the tree suggests that a common relationship between diurnal stem water storage capacity and tree size existed. These results are consistent with a recent hypothesis that allometric scaling of plant vascular systems, and therefore water use, is universal.

Semantic World Modelling and Data Management in a 4d Forest Simulation and Information System

NASA Astrophysics Data System (ADS)

Roßmann, J.; Hoppen, M.; Bücken, A.

2013-08-01

Various types of 3D simulation applications benefit from realistic forest models. They range from flight simulators for entertainment to harvester simulators for training and tree growth simulations for research and planning. Our 4D forest simulation and information system integrates the necessary methods for data extraction, modelling and management. Using modern methods of semantic world modelling, tree data can efficiently be extracted from remote sensing data. The derived forest models contain position, height, crown volume, type and diameter of each tree. This data is modelled using GML-based data models to assure compatibility and exchangeability. A flexible approach for database synchronization is used to manage the data and provide caching, persistence, a central communication hub for change distribution, and a versioning mechanism. Combining various simulation techniques and data versioning, the 4D forest simulation and information system can provide applications with "both directions" of the fourth dimension. Our paper outlines the current state, new developments, and integration of tree extraction, data modelling, and data management. It also shows several applications realized with the system.

Olive Actual "on Year" Yield Forecast Tool Based on the Tree Canopy Geometry Using UAS Imagery.

PubMed

Sola-Guirado, Rafael R; Castillo-Ruiz, Francisco J; Jiménez-Jiménez, Francisco; Blanco-Roldan, Gregorio L; Castro-Garcia, Sergio; Gil-Ribes, Jesus A

2017-07-30

Olive has a notable importance in countries of Mediterranean basin and its profitability depends on several factors such as actual yield, production cost or product price. Actual "on year" Yield (AY) is production (kg tree -1 ) in "on years", and this research attempts to relate it with geometrical parameters of the tree canopy. Regression equation to forecast AY based on manual canopy volume was determined based on data acquired from different orchard categories and cultivars during different harvesting seasons in southern Spain. Orthoimages were acquired with unmanned aerial systems (UAS) imagery calculating individual crown for relating to canopy volume and AY. Yield levels did not vary between orchard categories; however, it did between irrigated orchards (7000-17,000 kg ha -1 ) and rainfed ones (4000-7000 kg ha -1 ). After that, manual canopy volume was related with the individual crown area of trees that were calculated by orthoimages acquired with UAS imagery. Finally, AY was forecasted using both manual canopy volume and individual tree crown area as main factors for olive productivity. AY forecast only by using individual crown area made it possible to get a simple and cheap forecast tool for a wide range of olive orchards. Finally, the acquired information was introduced in a thematic map describing spatial AY variability obtained from orthoimage analysis that may be a powerful tool for farmers, insurance systems, market forecasts or to detect agronomical problems.

Soil management practices under organic farming

NASA Astrophysics Data System (ADS)

Aly, Adel; Chami Ziad, Al; Hamdy, Atef

2015-04-01

Organic farming methods combine scientific knowledge of ecology and modern technology with traditional farming practices based on naturally occurring biological processes. Soil building practices such as crop rotations, intercropping, symbiotic associations, cover crops, organic fertilizers and minimum tillage are central to organic practices. Those practices encourage soil formation and structure and creating more stable systems. In farm nutrient and energy cycling is increased and the retentive abilities of the soil for nutrients and water are enhanced. Such management techniques also play an important role in soil erosion control. The length of time that the soil is exposed to erosive forces is decreased, soil biodiversity is increased, and nutrient losses are reduced, helping to maintain and enhance soil productivity. Organic farming as systematized and certifiable approach for agriculture, there is no surprise that it faces some challenges among both farmers and public sector. This can be clearly demonstrated particularly in the absence of the essential conditions needed to implement successfully the soil management practices like green manure and composting to improve soil fertility including crop rotation, cover cropping and reduced tillage. Those issues beside others will be fully discussed highlighting their beneficial impact on the environmental soil characteristics. Keywords: soil fertility, organic matter, plant nutrition

Probabilistic Risk Assessment of Hydraulic Fracturing in Unconventional Reservoirs by Means of Fault Tree Analysis: An Initial Discussion

NASA Astrophysics Data System (ADS)

Rodak, C. M.; McHugh, R.; Wei, X.

2016-12-01

The development and combination of horizontal drilling and hydraulic fracturing has unlocked unconventional hydrocarbon reserves around the globe. These advances have triggered a number of concerns regarding aquifer contamination and over-exploitation, leading to scientific studies investigating potential risks posed by directional hydraulic fracturing activities. These studies, balanced with potential economic benefits of energy production, are a crucial source of information for communities considering the development of unconventional reservoirs. However, probabilistic quantification of the overall risk posed by hydraulic fracturing at the system level are rare. Here we present the concept of fault tree analysis to determine the overall probability of groundwater contamination or over-exploitation, broadly referred to as the probability of failure. The potential utility of fault tree analysis for the quantification and communication of risks is approached with a general application. However, the fault tree design is robust and can handle various combinations of regional-specific data pertaining to relevant spatial scales, geological conditions, and industry practices where available. All available data are grouped into quantity and quality-based impacts and sub-divided based on the stage of the hydraulic fracturing process in which the data is relevant as described by the USEPA. Each stage is broken down into the unique basic events required for failure; for example, to quantify the risk of an on-site spill we must consider the likelihood, magnitude, composition, and subsurface transport of the spill. The structure of the fault tree described above can be used to render a highly complex system of variables into a straightforward equation for risk calculation based on Boolean logic. This project shows the utility of fault tree analysis for the visual communication of the potential risks of hydraulic fracturing activities on groundwater resources.

Chemical Relationship On Detection Of Ganoderma Disease On Oil Palm Tree System

NASA Astrophysics Data System (ADS)

Imran, S. N. M.; Baharudin, F.; Ali, M. F.; Rahiman, M. H. F.

2018-04-01

Detection of fungal disease is the major issues in agricultural management and production. This disease would attack the plantation area and damaging the based root or the stem tissue of the trees. In oil palm industry, Basal Stem Rot (BSR) is the major disease in Malaysia that caused by a fungal named Ganoderma Boninense species. Since agricultural areas in Malaysia are the great factors that contribute in the economic sector, therefore the prevention and controlling this disease situation are needed to reduce the extent of the infection. These plant diseases are mostly being caused by the inflectional disease form such as viruses, viroids, bacteria, protozoa and even parasitic plants. It also could included mites and vertebrate or small insects that consume the plant tissues. Studies focused more on the breeding and relationship of the disease in the stumps, roots and soil system if oil palm trees by identifying the heavy metal; Phosphorus, copper, Iron, Manganese, Potassium and Zinc characteristic. Samples were taken from various types of physical appearance of the trees. It shows the relationship of the fungal disease breeding between oil palm trees and the heavy metals does affect the tree’s system.

Changes in Vegetation Reflect Changes in the Mammoth Mountain and Long Valley Caldera Hydrothermal System

NASA Astrophysics Data System (ADS)

Murphy, F.; Diefenbach, A. K.; Evans, W.; Hurwitz, S.

2013-12-01

We examined aerial photographs of the area near Mammoth Lakes, CA taken from 1951 to the present, with the goal of determining if visible changes in vegetation might reflect changes in the upflow of gas or heat through the soil zone. Such changes could be related to magmatic intrusion, the development of geothermal resources, groundwater pumping, earthquakes, or to natural changes in the hydrothermal flow system. We examined the area near Horseshoe Lake at the southern base of Mammoth Mountain where diffuse emissions of carbon dioxide created extensive tree-kill in the 1990s. Analysis of photographs acquired in 1951 suggests that tree density in this area was lower than its surroundings at the time. Whether the low-density tree cover identified in the photographs indicates some lasting effects of a previous episode of tree mortality needs further investigation. We also examine possible effects of geothermal energy production at Casa Diablo that began operation in 1985 on vegetation along the western part of the resurgent dome of Long Valley Caldera. Previous studies have correlated tree-kill in this area with increased steam upflow from the hydrothermal system.

A biologically-based individual tree model for managing the longleaf pine ecosystem

Treesearch

Rick Smith; Greg Somers

1998-01-01

Duration: 1995-present Objective: Develop a longleaf pine dynamics model and simulation system to define desirable ecosystem management practices in existing and future longleaf pine stands. Methods: Naturally-regenerated longleaf pine trees are being destructively sampled to measure their recent growth and dynamics. Soils and climate data will be combined with the...

Genetic subpopulation structuring and its implications in a mature eastern white pine stand

Treesearch

Samuel E. Nijensohn; Paul G. Schaberg; Gary J. Hawley; Donald H. DeHayes; Donald H. DeHayes

2005-01-01

We examined patterns of genetic structuring within a mature eastern white pine (Pinus strobus L.) forest, using geographic information system (GIS)-based data and maps that combined genetic (isozyme analysis of 46 loci) and other tree-specific information (e.g., size, growth, age, and location) for 220 trees in Jericho, Vermont. Interconnections between genotypic...

Gene and enhancer trap tagging of vascular-expressed genes in poplar trees

Treesearch

Andrew Groover; Joseph R. Fontana; Gayle Dupper; Caiping Ma; Robert Martienssen; Steven Strauss; Richard Meilan

2004-01-01

We report a gene discovery system for poplar trees based on gene and enhancer traps. Gene and enhancer trap vectors carrying the β-glucuronidase (GUS) reporter gene were inserted into the poplar genome via Agrobacterium tumefaciens transformation, where they reveal the expression pattern of genes at or near the insertion sites. Because GUS...

Discovering Decision Knowledge from Web Log Portfolio for Managing Classroom Processes by Applying Decision Tree and Data Cube Technology.

ERIC Educational Resources Information Center

Chen, Gwo-Dong; Liu, Chen-Chung; Ou, Kuo-Liang; Liu, Baw-Jhiune

2000-01-01

Discusses the use of Web logs to record student behavior that can assist teachers in assessing performance and making curriculum decisions for distance learning students who are using Web-based learning systems. Adopts decision tree and data cube information processing methodologies for developing more effective pedagogical strategies. (LRW)

Automated diagnosis of coronary artery disease based on data mining and fuzzy modeling.

PubMed

Tsipouras, Markos G; Exarchos, Themis P; Fotiadis, Dimitrios I; Kotsia, Anna P; Vakalis, Konstantinos V; Naka, Katerina K; Michalis, Lampros K

2008-07-01

A fuzzy rule-based decision support system (DSS) is presented for the diagnosis of coronary artery disease (CAD). The system is automatically generated from an initial annotated dataset, using a four stage methodology: 1) induction of a decision tree from the data; 2) extraction of a set of rules from the decision tree, in disjunctive normal form and formulation of a crisp model; 3) transformation of the crisp set of rules into a fuzzy model; and 4) optimization of the parameters of the fuzzy model. The dataset used for the DSS generation and evaluation consists of 199 subjects, each one characterized by 19 features, including demographic and history data, as well as laboratory examinations. Tenfold cross validation is employed, and the average sensitivity and specificity obtained is 62% and 54%, respectively, using the set of rules extracted from the decision tree (first and second stages), while the average sensitivity and specificity increase to 80% and 65%, respectively, when the fuzzification and optimization stages are used. The system offers several advantages since it is automatically generated, it provides CAD diagnosis based on easily and noninvasively acquired features, and is able to provide interpretation for the decisions made.

Development of a methodology for assessing the safety of embedded software systems

NASA Technical Reports Server (NTRS)

Garrett, C. J.; Guarro, S. B.; Apostolakis, G. E.

1993-01-01

A Dynamic Flowgraph Methodology (DFM) based on an integrated approach to modeling and analyzing the behavior of software-driven embedded systems for assessing and verifying reliability and safety is discussed. DFM is based on an extension of the Logic Flowgraph Methodology to incorporate state transition models. System models which express the logic of the system in terms of causal relationships between physical variables and temporal characteristics of software modules are analyzed to determine how a certain state can be reached. This is done by developing timed fault trees which take the form of logical combinations of static trees relating the system parameters at different point in time. The resulting information concerning the hardware and software states can be used to eliminate unsafe execution paths and identify testing criteria for safety critical software functions.

Growth, biomass production and photosynthesis of Cenchrus ciliaris L. under Acacia tortilis (Forssk.) Hayne based silvopastoral systems in semi arid tropics.

PubMed

Mishra, A K; Tiwari, H S; Bhatt, R K

2010-11-01

The growth, biomass production and photosynthesis of Cenchrus ciliaris was studied under the canopies of 17 yr old Acacia tortilis trees in semi arid tropical environment. On an average the full grown canopy of A. tortilis at the spacing of 4 x 4 m allowed 55% of total Photosynthetically Active Radiation (PAR) which in turn increased Relative Humidity (RH) and reduced under canopy temperature to -1.75 degrees C over the open air temperature. C. ciliaris attained higher height under the shade of A. tortilis. The tiller production and leaf area index decreased marginally under the shade of tree canopies as compared to the open grown grasses. C. ciliaris accumulated higher chlorophyll a and b under the shade of tree canopies indicating its shade adaptation potential. The assimilatory functions such as rate of photosynthesis, transpiration, stomatal conductance, photosynthetic water use efficiency (PN/TR) and carboxylation efficiency (PN/CINT) decreased under the tree canopies due to low availability of PAR. The total biomass production in term of fresh and dry weight decreased under the tree canopies. On average of 2 yr C. ciliaris had produced 12.78 t ha(-1) green and 3.72 -t ha(-1) dry biomass under the tree canopies of A. tortilis. The dry matter yield reduced to 38% under the tree canopies over the open grown grasses. The A. tortilis + C. ciliaris maintained higher soil moisture, organic carbon content and available N P K for sustainable biomass production for the longer period. The higher accumulation of crude protein, starch, sugar and nitrogen in leaves and stem of C. ciliaris indicates that this grass species also maintained its quality under A. tortilis based silvopastoral system. The photosynthesis and dry matter accumulation are closely associated with available PAR indicating that for sustainable production of this grass species in the silvopasture systems for longer period about 55% or more PAR is required.

Probabilistic fault tree analysis of a radiation treatment system.

PubMed

Ekaette, Edidiong; Lee, Robert C; Cooke, David L; Iftody, Sandra; Craighead, Peter

2007-12-01

Inappropriate administration of radiation for cancer treatment can result in severe consequences such as premature death or appreciably impaired quality of life. There has been little study of vulnerable treatment process components and their contribution to the risk of radiation treatment (RT). In this article, we describe the application of probabilistic fault tree methods to assess the probability of radiation misadministration to patients at a large cancer treatment center. We conducted a systematic analysis of the RT process that identified four process domains: Assessment, Preparation, Treatment, and Follow-up. For the Preparation domain, we analyzed possible incident scenarios via fault trees. For each task, we also identified existing quality control measures. To populate the fault trees we used subjective probabilities from experts and compared results with incident report data. Both the fault tree and the incident report analysis revealed simulation tasks to be most prone to incidents, and the treatment prescription task to be least prone to incidents. The probability of a Preparation domain incident was estimated to be in the range of 0.1-0.7% based on incident reports, which is comparable to the mean value of 0.4% from the fault tree analysis using probabilities from the expert elicitation exercise. In conclusion, an analysis of part of the RT system using a fault tree populated with subjective probabilities from experts was useful in identifying vulnerable components of the system, and provided quantitative data for risk management.

Biocompatibility of sweetpotato and peanut in a hydroponic system

NASA Technical Reports Server (NTRS)

Mortley, D. G.; Loretan, P. A.; Hill, W. A.; Bonsi, C. K.; Morris, C. E.; Hall, R.; Sullen, D.

1998-01-01

'Georgia Red' peanut (Arachis hypogaea L.) and TU-82-155 sweetpotato [Ipomoea batatas (L.) Lam] were grown in monocultured or intercropped recirculating hydroponic systems in a greenhouse using the nutrient film technique (NFT). The objective was to determine whether growth and subsequent yield would be affected by intercropping. Treatments were sweetpotato monoculture (SP), peanut monoculture (PN), and sweetpotato and peanut grown in separate NFT channels but sharing a common nutrient solution (SP-PN). Greenhouse conditions ranged from 24 to 33 degrees C, 60% to 90% relative humidity (RH), and photosynthetic photon flux (PPF) of 200 to 1700 micromoles m-2 s-1. Sweetpotato cuttings (15 cm long) and 14-day-old seedlings of peanuts were planted into growth channels (0.15 x 0.15 x 1.2 m). Plants were spaced 25 cm apart within and 25 cm apart between growing channels. A modified half-Hoagland solution with a 1 N: 2.4 K ratio was used. Solution pH was maintained between 5.5 and 6.0 for treatments involving SP and 6.4 and 6.7 for PN. Electrical conductivity (EC) ranged between 1100 and 1200 microS cm-1. The number of storage roots per sweetpotato plant was similar for both SP and SP-PN. Storage root fresh and dry mass were 29% and 36% greater, respectively, for plants in the SP-PN treatment than for plants in the SP treatment. The percent dry mass of the storage roots, dry mass of fibrous and pencil roots, and the length-to-diameter ratio of storage roots were similar for SP and SP-PN sweetpotato plants. Likewise, foliage fresh and dry mass and harvest index were not significantly influenced by treatment. Total dry mass was 37% greater for PN than for SP-PN peanut plants, and pod dry mass was 82% higher. Mature and total seed dry mass and fibrous root dry mass were significantly greater for PN than for SP-PN plants. Harvest index (HI) was similar for both treatments. Root length tended to be lower for seedlings grown in the nutrient solution from the SP-PN treatment.

Competitive code-based fast palmprint identification using a set of cover trees

NASA Astrophysics Data System (ADS)

Yue, Feng; Zuo, Wangmeng; Zhang, David; Wang, Kuanquan

2009-06-01

A palmprint identification system recognizes a query palmprint image by searching for its nearest neighbor from among all the templates in a database. When applied on a large-scale identification system, it is often necessary to speed up the nearest-neighbor searching process. We use competitive code, which has very fast feature extraction and matching speed, for palmprint identification. To speed up the identification process, we extend the cover tree method and propose to use a set of cover trees to facilitate the fast and accurate nearest-neighbor searching. We can use the cover tree method because, as we show, the angular distance used in competitive code can be decomposed into a set of metrics. Using the Hong Kong PolyU palmprint database (version 2) and a large-scale palmprint database, our experimental results show that the proposed method searches for nearest neighbors faster than brute force searching.

Wind-Induced Reconfigurations in Flexible Branched Trees

NASA Astrophysics Data System (ADS)

Ojo, Oluwafemi; Shoele, Kourosh

2017-11-01

Wind induced stresses are the major mechanical cause of failure in trees. We know that the branching mechanism has an important effect on the stress distribution and stability of a tree in the wind. Eloy in PRL 2011, showed that Leonardo da Vinci's original observation which states the total cross section of branches is conserved across branching nodes is the best configuration for resisting wind-induced fracture in rigid trees. However, prediction of the fracture risk and pattern of a tree is also a function of their reconfiguration capabilities and how they mitigate large wind-induced stresses. In this studies through developing an efficient numerical simulation of flexible branched trees, we explore the role of the tree flexibility on the optimal branching. Our results show that the probability of a tree breaking at any point depends on both the cross-section changes in the branching nodes and the level of tree flexibility. It is found that the branching mechanism based on Leonardo da Vinci's original observation leads to a uniform stress distribution over a wide range of flexibilities but the pattern changes for more flexible systems.

iTREE: Long-term variability of tree growth in a changing environment - identifying physiological mechanisms using stable C and O isotopes in tree rings.

NASA Astrophysics Data System (ADS)

Siegwolf, R. T. W.; Buchmann, N.; Frank, D.; Joos, F.; Kahmen, A.; Treydte, K.; Leuenberger, M.; Saurer, M.

2012-04-01

Trees play are a critical role in the carbon cycle - their photosynthetic assimilation is one of the largest terrestrial carbon fluxes and their standing biomass represents the largest carbon pool of the terrestrial biosphere. Understanding how tree physiology and growth respond to long-term environmental change is pivotal to predict the magnitude and direction of the terrestrial carbon sink. iTREE is an interdisciplinary research framework to capitalize on synergies among leading dendroclimatologists, plant physiologists, isotope specialists, and global carbon cycle modelers with the objectives of reducing uncertainties related to tree/forest growth in the context of changing natural environments. Cross-cutting themes in our project are tree rings, stable isotopes, and mechanistic modelling. We will (i) establish a European network of tree-ring based isotope time-series to retrodict interannual to long-term tree physiological changes, (ii) conduct laboratory and field experiments to adapt a mechanistic isotope model to derive plant physiological variables from tree-ring isotopes, (iii) implement this model into a dynamic global vegetation model, and perform subsequent model-data validation exercises to refine model representation of plant physiological processes and (iv) attribute long-term variation in tree growth to plant physiological and environmental drivers, and identify how our refined knowledge revises predictions of the coupled carbon-cycle climate system. We will contribute to i) advanced quantifications of long-term variation in tree growth across Central Europe, ii) novel long-term information on key physiological processes that underlie variations in tree growth, and iii) improved carbon cycle models that can be employed to revise predictions of the coupled carbon-cycle climate system. Hence iTREE will significantly contribute towards a seamless understanding of the responses of terrestrial ecosystems to long-term environmental change, and ultimately help reduce uncertainties of the magnitude and direction of the past and future terrestrial carbon sink.

Policy Tree Optimization for Adaptive Management of Water Resources Systems

NASA Astrophysics Data System (ADS)

Herman, J. D.; Giuliani, M.

2016-12-01

Water resources systems must cope with irreducible uncertainty in supply and demand, requiring policy alternatives capable of adapting to a range of possible future scenarios. Recent studies have developed adaptive policies based on "signposts" or "tipping points", which are threshold values of indicator variables that signal a change in policy. However, there remains a need for a general method to optimize the choice of indicators and their threshold values in a way that is easily interpretable for decision makers. Here we propose a conceptual framework and computational algorithm to design adaptive policies as a tree structure (i.e., a hierarchical set of logical rules) using a simulation-optimization approach based on genetic programming. We demonstrate the approach using Folsom Reservoir, California as a case study, in which operating policies must balance the risk of both floods and droughts. Given a set of feature variables, such as reservoir level, inflow observations and forecasts, and time of year, the resulting policy defines the conditions under which flood control and water supply hedging operations should be triggered. Importantly, the tree-based rule sets are easy to interpret for decision making, and can be compared to historical operating policies to understand the adaptations needed under possible climate change scenarios. Several remaining challenges are discussed, including the empirical convergence properties of the method, and extensions to irreversible decisions such as infrastructure. Policy tree optimization, and corresponding open-source software, provide a generalizable, interpretable approach to designing adaptive policies under uncertainty for water resources systems.

Field note: irrigation of tree stands with groundwater containing 1,4-dioxane.

PubMed

Ferro, Ari M; Tammi, Carl E

2009-07-01

Coniferous and deciduous tree stands totaling 14 ha were recently planted on a closed landfill, and when mature, the stands are expected to be part of a natural treatment system for recovered groundwater. The trees would be irrigated at the rate of 189 L/min year-round with water containing 1,4-dioxane (< 10 mg/L), a compound that would be taken up and phytovolatilized by the trees. The water is moderately saline and contains elevated levels of manganese. This paper describes a concurrent series of preliminary studies, performed prior to the full-scale planting, to assess the feasibility of the phytoremediation system. Greenhouse experiments were carried out to identify tree species that can take up 1,4-dioxane and are tolerant of the water. Estimates were made of the area of the tree stand necessary to transpire the irrigation water plus precipitation. The landfill matrix was characterized in terms of its percolation rate and water holding capacity and based on those results salinity-modeling studies were carried out to estimate the fate and leaching potential of the various inorganic species that would accumulate in the root-zone of the trees. A pilot study, currently in progress on the landfill, suggested that the landfill cap is a suitable matrix for the establishment of large trees, and that the stands could be irrigated without the production of excess drainage.

Evaluation of growth disturbances of Picea abies (L.) Karst. to disturbances caused by landslide movements

NASA Astrophysics Data System (ADS)

Šilhán, Karel

2017-01-01

Dendrogeomorphic methods are frequently used in landslide analyses. Although methods of landslide dating based on tree rings are well developed, they still indicated many questions. The aim of this study was to evaluate the frequently used theoretical scheme based on the event-response relationship. Seventy-four individuals of Norway spruce (Picea abies (L.) Karst.) exhibiting visible external disturbance, were sampled on the Girová landslide (the largest historical flow-like landslide in the Czech Republic). This landslide reactivated in May 2010, and post-landslide tree growth responses were studied in detail. These growth responses were compared with the intensity and occurrence of visible external tree disturbance: tilted stems, damaged root systems, and decapitation. Twenty-nine trees (39.2%) died within one to four years following the 2010 landslide movement. The trees that died following the landslide movement were significantly younger and displayed significantly greater stem tilting than the live trees. Abrupt growth suppression was a more-frequent response among the dead trees, whereas growth release dominated among the live trees. Only two trees (2.7%) created no reaction wood in response to the landslide movement. Forty-four percent of the trees started to produce reaction wood structure after a delay, which generally spanned one year. Some eccentric growth was evident in the tree rings of the landslide year and was significant in the first years following the landslide movement. Missing rings were observed only on the upper sides of the stems, and no false tree rings were observed. The results confirm the general validity of event-response relationship, nevertheless this study points out the limitations and uncertainties of this generally accepted working scheme.

MANPRINT Methods Monograph: Aiding the Development of Manpower-Based System Evaluation

DTIC Science & Technology

1989-06-01

zone below tree level where threats are known to be (the actual number of threats may vary). Weather conditions are VFR. The helicopter pops up to...12.0 Replace 13.3 Bearing, connecting Inspect 6.2 Replace 6.2 0105 Camshaft Inspect 7.2 Replace 7.2 Cover, cylinder head Inspect .2 (valve cover...matrix to analyze the data and identify task clusters. . Outputs and Use of Cluster Analysis 1. Hierarchical cluster tree (taxonomy) of system tasks will

Soil properties determine the elevational patterns of base cations and micronutrients in the plant-soil system up to the upper limits of trees and shrubs

NASA Astrophysics Data System (ADS)

Wang, Ruzhen; Wang, Xue; Jiang, Yong; Cerdà, Artemi; Yin, Jinfei; Liu, Heyong; Feng, Xue; Shi, Zhan; Dijkstra, Feike A.; Li, Mai-He

2018-03-01

To understand whether base cations and micronutrients in the plant-soil system change with elevation, we investigated the patterns of base cations and micronutrients in both soils and plant tissues along three elevational gradients in three climate zones in China. Base cations (Ca, Mg, and K) and micronutrients (Fe, Mn, and Zn) were determined in soils, trees, and shrubs growing at lower and middle elevations as well as at their upper limits on Balang (subtropical, SW China), Qilian (dry temperate, NW China), and Changbai (wet temperate, NE China) mountains. No consistent elevational patterns were found for base cation and micronutrient concentrations in both soils and plant tissues (leaves, roots, shoots, and stem sapwood). Soil pH, soil organic carbon (SOC), total soil nitrogen (TN), the SOC to TN ratio (C : N), and soil extractable nitrogen (NO3- and NH4+) determined the elevational patterns of soil exchangeable Ca and Mg and available Fe, Mn, and Zn. However, the controlling role of soil pH and SOC was not universal as revealed by their weak correlations with soil base cations under tree canopies at the wet temperate mountain and with micronutrients under both tree and shrub canopies at the dry temperate mountain. In most cases, soil base cation and micronutrient availabilities played fundamental roles in determining the base cation and micronutrient concentrations in plant tissues. An exception existed for the decoupling of leaf K and Fe with their availabilities in the soil. Our results highlight the importance of soil physicochemical properties (mainly SOC, C : N, and pH) rather than elevation (i.e., canopy cover and environmental factors, especially temperature), in determining base cation and micronutrient availabilities in soils and subsequently their concentrations in plant tissues.

Modelling the effects of cutting off infected branches and replanting on fire-blight transmission using Filippov systems.

PubMed

Chen, Can; Li, Chentong; Kang, Yanmei

2018-02-14

Fire blight is one of the most devastating plant diseases in the world. This paper proposes a Filippov fire-blight model incorporating cutting off infected branches and replanting susceptible trees. The Filippov-type model is formulated by considering that no control strategy is taken if the number of infected trees is less than an infected threshold level I c ; further, we cut off infected branches once the number of infected trees exceeds I c ; meanwhile, we replant trees if the number of susceptible trees is less than a susceptible threshold level S c . The global dynamical behaviour of the Filippov system is investigated. It is shown that model solutions ultimately converge to the positive equilibrium that lies in the region above I c , or below I c , or on I=I c , as we vary the susceptible and infected threshold values S c and I c . Our results indicate that proper combinations of the susceptible and infected threshold values based on the threshold policy can lead the number of infected trees to an acceptable level, when complete eradication is not economically desirable. Copyright © 2017 Elsevier Ltd. All rights reserved.

Economics of intercropping loblolly pine and switchgrass for bioenergy markets in the southeastern United States

Treesearch

Andres Susaeta; Janaki Alavalapati Pankaj Lal; D. Evan Mercer; Douglas Carter

2012-01-01

Abstract The main objective of this study was to assess the economics of alley cropping of loblolly pine (Pinus taeda L.) and switchgrass (Panicum virgatum) in the southern United States. Assuming a price range of switchgrass between $15 and $50 Mg-1 and yield of 12 Mg ha-1 year-1, we investigated the effect of switchgrass production on the optimal forest management...

Development of a diagnostic decision tree for obstructive pulmonary diseases based on real-life data

PubMed Central

in ’t Veen, Johannes C.C.M.; Dekhuijzen, P.N. Richard; van Heijst, Ellen; Kocks, Janwillem W.H.; Muilwijk-Kroes, Jacqueline B.; Chavannes, Niels H.; van der Molen, Thys

2016-01-01

The aim of this study was to develop and explore the diagnostic accuracy of a decision tree derived from a large real-life primary care population. Data from 9297 primary care patients (45% male, mean age 53±17 years) with suspicion of an obstructive pulmonary disease was derived from an asthma/chronic obstructive pulmonary disease (COPD) service where patients were assessed using spirometry, the Asthma Control Questionnaire, the Clinical COPD Questionnaire, history data and medication use. All patients were diagnosed through the Internet by a pulmonologist. The Chi-squared Automatic Interaction Detection method was used to build the decision tree. The tree was externally validated in another real-life primary care population (n=3215). Our tree correctly diagnosed 79% of the asthma patients, 85% of the COPD patients and 32% of the asthma–COPD overlap syndrome (ACOS) patients. External validation showed a comparable pattern (correct: asthma 78%, COPD 83%, ACOS 24%). Our decision tree is considered to be promising because it was based on real-life primary care patients with a specialist's diagnosis. In most patients the diagnosis could be correctly predicted. Predicting ACOS, however, remained a challenge. The total decision tree can be implemented in computer-assisted diagnostic systems for individual patients. A simplified version of this tree can be used in daily clinical practice as a desk tool. PMID:27730177

Remnant Pachira quinata pasture trees have greater opportunities to self and suffer reduced reproductive success due to inbreeding depression.

PubMed

Rymer, P D; Sandiford, M; Harris, S A; Billingham, M R; Boshier, D H

2015-08-01

Habitat fragmentation is extensive throughout the world, converting natural ecosystems into fragments of varying size, density and connectivity. The potential value of remnant trees in agricultural landscapes as seed sources and in connecting fragments has formed a fertile area of debate. This study contrasted the mating patterns of bat-pollinated Pachira quinata trees in a continuous forest to those in pasture through microsatellite-based paternity analysis of progeny. The breeding system was determined by analysis of pollen tube growth and seed production from controlled pollinations. Fitness of selfed and outcrossed seed was compared by germination and seedling growth. There was more inbreeding within pasture trees (outcrossing=0.828±0.015) compared with forest trees (0.926±0.005). Pasture trees had fewer sires contributing to mating events, but pollen dispersal distances were greater than those in the forest. Paternity analysis showed variation in outcrossing rates among pasture trees with high proportions of external and self pollen sources detected. A leaky self-incompatibility system was found, with self pollen having reduced germination on stigmas and slower growth rate through the style. Controlled pollinations also showed a varied ability to self among trees, which was reflected in the selfing rates among pasture trees shown by the paternity analysis (0-80% selfing). Self pollination resulted in lower seed set, germination and seedling growth compared with outcrossing. While remnant trees in agricultural landscapes are involved in broader mating patterns, they show increased but varied levels of inbreeding, which result in reduced fitness.

Automatic tree parameter extraction by a Mobile LiDAR System in an urban context.

PubMed

Herrero-Huerta, Mónica; Lindenbergh, Roderik; Rodríguez-Gonzálvez, Pablo

2018-01-01

In an urban context, tree data are used in city planning, in locating hazardous trees and in environmental monitoring. This study focuses on developing an innovative methodology to automatically estimate the most relevant individual structural parameters of urban trees sampled by a Mobile LiDAR System at city level. These parameters include the Diameter at Breast Height (DBH), which was estimated by circle fitting of the points belonging to different height bins using RANSAC. In the case of non-circular trees, DBH is calculated by the maximum distance between extreme points. Tree sizes were extracted through a connectivity analysis. Crown Base Height, defined as the length until the bottom of the live crown, was calculated by voxelization techniques. For estimating Canopy Volume, procedures of mesh generation and α-shape methods were implemented. Also, tree location coordinates were obtained by means of Principal Component Analysis. The workflow has been validated on 29 trees of different species sampling a stretch of road 750 m long in Delft (The Netherlands) and tested on a larger dataset containing 58 individual trees. The validation was done against field measurements. DBH parameter had a correlation R2 value of 0.92 for the height bin of 20 cm which provided the best results. Moreover, the influence of the number of points used for DBH estimation, considering different height bins, was investigated. The assessment of the other inventory parameters yield correlation coefficients higher than 0.91. The quality of the results confirms the feasibility of the proposed methodology, providing scalability to a comprehensive analysis of urban trees.

Remnant Pachira quinata pasture trees have greater opportunities to self and suffer reduced reproductive success due to inbreeding depression

PubMed Central

Rymer, P D; Sandiford, M; Harris, S A; Billingham, M R; Boshier, D H

2015-01-01

Habitat fragmentation is extensive throughout the world, converting natural ecosystems into fragments of varying size, density and connectivity. The potential value of remnant trees in agricultural landscapes as seed sources and in connecting fragments has formed a fertile area of debate. This study contrasted the mating patterns of bat-pollinated Pachira quinata trees in a continuous forest to those in pasture through microsatellite-based paternity analysis of progeny. The breeding system was determined by analysis of pollen tube growth and seed production from controlled pollinations. Fitness of selfed and outcrossed seed was compared by germination and seedling growth. There was more inbreeding within pasture trees (outcrossing=0.828±0.015) compared with forest trees (0.926±0.005). Pasture trees had fewer sires contributing to mating events, but pollen dispersal distances were greater than those in the forest. Paternity analysis showed variation in outcrossing rates among pasture trees with high proportions of external and self pollen sources detected. A leaky self-incompatibility system was found, with self pollen having reduced germination on stigmas and slower growth rate through the style. Controlled pollinations also showed a varied ability to self among trees, which was reflected in the selfing rates among pasture trees shown by the paternity analysis (0–80% selfing). Self pollination resulted in lower seed set, germination and seedling growth compared with outcrossing. While remnant trees in agricultural landscapes are involved in broader mating patterns, they show increased but varied levels of inbreeding, which result in reduced fitness. PMID:23963342

Automatic tree parameter extraction by a Mobile LiDAR System in an urban context

PubMed Central

Lindenbergh, Roderik; Rodríguez-Gonzálvez, Pablo

2018-01-01

In an urban context, tree data are used in city planning, in locating hazardous trees and in environmental monitoring. This study focuses on developing an innovative methodology to automatically estimate the most relevant individual structural parameters of urban trees sampled by a Mobile LiDAR System at city level. These parameters include the Diameter at Breast Height (DBH), which was estimated by circle fitting of the points belonging to different height bins using RANSAC. In the case of non-circular trees, DBH is calculated by the maximum distance between extreme points. Tree sizes were extracted through a connectivity analysis. Crown Base Height, defined as the length until the bottom of the live crown, was calculated by voxelization techniques. For estimating Canopy Volume, procedures of mesh generation and α-shape methods were implemented. Also, tree location coordinates were obtained by means of Principal Component Analysis. The workflow has been validated on 29 trees of different species sampling a stretch of road 750 m long in Delft (The Netherlands) and tested on a larger dataset containing 58 individual trees. The validation was done against field measurements. DBH parameter had a correlation R2 value of 0.92 for the height bin of 20 cm which provided the best results. Moreover, the influence of the number of points used for DBH estimation, considering different height bins, was investigated. The assessment of the other inventory parameters yield correlation coefficients higher than 0.91. The quality of the results confirms the feasibility of the proposed methodology, providing scalability to a comprehensive analysis of urban trees. PMID:29689076

Indirect effects of ecosystem engineering combine with consumer behaviour to determine the spatial distribution of herbivory.

PubMed

Griffen, Blaine D; Riley, Megan E; Cannizzo, Zachary J; Feller, Ilka C

2017-10-01

Ecosystem engineers alter environments by creating, modifying or destroying habitats. The indirect impacts of ecosystem engineering on trophic interactions should depend on the combination of the spatial distribution of engineered structures and the foraging behaviour of consumers that use these structures as refuges. In this study, we assessed the indirect effects of ecosystem engineering by a wood-boring beetle in a neotropical mangrove forest system. We identified herbivory patterns in a dwarf mangrove forest on the archipelago of Twin Cays, Belize. Past wood-boring activity impacted more than one-third of trees through the creation of tree holes that are now used, presumably as predation or thermal refuge, by the herbivorous mangrove tree crab Aratus pisonii. The presence of these refuges had a significant impact on plant-animal interactions; herbivory was more than fivefold higher on trees influenced by tree holes relative to those that were completely isolated from these refuges. Additionally, herbivory decreased exponentially with increasing distance from tree holes. We use individual-based simulation modelling to demonstrate that the creation of these herbivory patterns depends on a combination of the use of engineered tree holes for refuge by tree crabs, and the use of two behaviour patterns in this species-site fidelity to a "home tree," and more frequent foraging near their home tree. We demonstrate that understanding the spatial distribution of herbivory in this system depends on combining both the use of ecosystem engineering structures with individual behavioural patterns of herbivores. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Application Research of Fault Tree Analysis in Grid Communication System Corrective Maintenance

NASA Astrophysics Data System (ADS)

Wang, Jian; Yang, Zhenwei; Kang, Mei

2018-01-01

This paper attempts to apply the fault tree analysis method to the corrective maintenance field of grid communication system. Through the establishment of the fault tree model of typical system and the engineering experience, the fault tree analysis theory is used to analyze the fault tree model, which contains the field of structural function, probability importance and so on. The results show that the fault tree analysis can realize fast positioning and well repairing of the system. Meanwhile, it finds that the analysis method of fault tree has some guiding significance to the reliability researching and upgrading f the system.

An improved classification tree analysis of high cost modules based upon an axiomatic definition of complexity

NASA Technical Reports Server (NTRS)

Tian, Jianhui; Porter, Adam; Zelkowitz, Marvin V.

1992-01-01

Identification of high cost modules has been viewed as one mechanism to improve overall system reliability, since such modules tend to produce more than their share of problems. A decision tree model was used to identify such modules. In this current paper, a previously developed axiomatic model of program complexity is merged with the previously developed decision tree process for an improvement in the ability to identify such modules. This improvement was tested using data from the NASA Software Engineering Laboratory.

UV-laser-based microscopic dissection of tree rings - a novel sampling tool for δ(13) C and δ(18) O studies.

PubMed

Schollaen, Karina; Heinrich, Ingo; Helle, Gerhard

2014-02-01

UV-laser-based microscopic systems were utilized to dissect and sample organic tissue for stable isotope measurements from thin wood cross-sections. We tested UV-laser-based microscopic tissue dissection in practice for high-resolution isotopic analyses (δ(13) C/δ(18) O) on thin cross-sections from different tree species. The method allows serial isolation of tissue of any shape and from millimetre down to micrometre scales. On-screen pre-defined areas of interest were automatically dissected and collected for mass spectrometric analysis. Three examples of high-resolution isotopic analyses revealed that: in comparison to δ(13) C of xylem cells, woody ray parenchyma of deciduous trees have the same year-to-year variability, but reveal offsets that are opposite in sign depending on whether wholewood or cellulose is considered; high-resolution tree-ring δ(18) O profiles of Indonesian teak reflect monsoonal rainfall patterns and are sensitive to rainfall extremes caused by ENSO; and seasonal moisture signals in intra-tree-ring δ(18) O of white pine are weighted by nonlinear intra-annual growth dynamics. The applications demonstrate that the use of UV-laser-based microscopic dissection allows for sampling plant tissue at ultrahigh resolution and unprecedented precision. This new technique facilitates sampling for stable isotope analysis of anatomical plant traits like combined tree eco-physiological, wood anatomical and dendroclimatological studies. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

[Hydraulic limitation on photosynthetic rate of old Populus simonii trees in sandy soil of north Shaanxi Province].

PubMed

Zuo, Li-Xiang; Li, Yang-Yang; Chen, Jia-Cun

2014-06-01

'Old and dwarf trees' on the loess plateau region mainly occurred among mature trees rather than among small trees. To elucidate the mechanism of tree age on 'old and dwarf trees' formation, taking Populus simonii, a tree species that accounted for the largest portion of 'old and dwarf trees' on the loess plateau, as an example, the growth, photosynthesis and hydraulic traits of P. simonii trees with different ages (young: 13-15 years, mid-aged: 31-34 years, and old: 49-54 years) were measured. The results showed that the dieback length increased, and net photosynthetic rate, stomatal conductance, transpiration rate, and whole plant hydraulic conductance decreased significantly with the increasing tree age. Both net photosynthetic rate and stomatal conductance measured at different dates were significantly and positively related to the whole plant hydraulic conductance, suggesting that the decreasing photosynthetic rate of old trees was possibly caused by the declined hydraulic conductance. Although the resistance to cavitation in stems and leaves was stronger in old trees than in young and mid-aged trees, there were no differences in midday native stem embolization degree and leaf hydraulic conductance based on the vulnerability curve estimation, suggesting that the increased hydraulic resistance of the soil-root system is probably the most important reason for decreasing the whole plant hydraulic conductance of old trees.

Efficient Construction of Mesostate Networks from Molecular Dynamics Trajectories.

PubMed

Vitalis, Andreas; Caflisch, Amedeo

2012-03-13

The coarse-graining of data from molecular simulations yields conformational space networks that may be used for predicting the system's long time scale behavior, to discover structural pathways connecting free energy basins in the system, or simply to represent accessible phase space regions of interest and their connectivities in a two-dimensional plot. In this contribution, we present a tree-based algorithm to partition conformations of biomolecules into sets of similar microstates, i.e., to coarse-grain trajectory data into mesostates. On account of utilizing an architecture similar to that of established tree-based algorithms, the proposed scheme operates in near-linear time with data set size. We derive expressions needed for the fast evaluation of mesostate properties and distances when employing typical choices for measures of similarity between microstates. Using both a pedagogically useful and a real-word application, the algorithm is shown to be robust with respect to tree height, which in addition to mesostate threshold size is the main adjustable parameter. It is demonstrated that the derived mesostate networks can preserve information regarding the free energy basins and barriers by which the system is characterized.

Method of center localization for objects containing concentric arcs

NASA Astrophysics Data System (ADS)

Kuznetsova, Elena G.; Shvets, Evgeny A.; Nikolaev, Dmitry P.

2015-02-01

This paper proposes a method for automatic center location of objects containing concentric arcs. The method utilizes structure tensor analysis and voting scheme optimized with Fast Hough Transform. Two applications of the proposed method are considered: (i) wheel tracking in video-based system for automatic vehicle classification and (ii) tree growth rings analysis on a tree cross cut image.

Towards organ printing: engineering an intra-organ branched vascular tree.

PubMed

Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

2010-03-01

Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a 'built in' intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a 'built in' intra-organ branched vascular tree.

A splay tree-based approach for efficient resource location in P2P networks.

PubMed

Zhou, Wei; Tan, Zilong; Yao, Shaowen; Wang, Shipu

2014-01-01

Resource location in structured P2P system has a critical influence on the system performance. Existing analytical studies of Chord protocol have shown some potential improvements in performance. In this paper a splay tree-based new Chord structure called SChord is proposed to improve the efficiency of locating resources. We consider a novel implementation of the Chord finger table (routing table) based on the splay tree. This approach extends the Chord finger table with additional routing entries. Adaptive routing algorithm is proposed for implementation, and it can be shown that hop count is significantly minimized without introducing any other protocol overheads. We analyze the hop count of the adaptive routing algorithm, as compared to Chord variants, and demonstrate sharp upper and lower bounds for both worst-case and average case settings. In addition, we theoretically analyze the hop reducing in SChord and derive the fact that SChord can significantly reduce the routing hops as compared to Chord. Several simulations are presented to evaluate the performance of the algorithm and support our analytical findings. The simulation results show the efficiency of SChord.

Conversion from Tree to Graph Representation of Requirements

NASA Technical Reports Server (NTRS)

Mayank, Vimal; Everett, David Frank; Shmunis, Natalya; Austin, Mark

2009-01-01

A procedure and software to implement the procedure have been devised to enable conversion from a tree representation to a graph representation of the requirements governing the development and design of an engineering system. The need for this procedure and software and for other requirements-management tools arises as follows: In systems-engineering circles, it is well known that requirements- management capability improves the likelihood of success in the team-based development of complex systems involving multiple technological disciplines. It is especially desirable to be able to visualize (in order to identify and manage) requirements early in the system- design process, when errors can be corrected most easily and inexpensively.

The Garden Banks 388 horizontal tree design and development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Granhaug, O.; Soul, J.

1995-12-31

This paper describes the Horizontal Subsea Production Tree System, later referred to as a SpoolTree{trademark}, developed for the Enserch Garden Banks 388 field in the Gulf of Mexico. The paper starts with a project overview followed by a comparison between the SpoolTree and the Conventional Tree design. A brief discussion explains why Enserch elected to use the SpoolTree for this field development, including available technology, workover frequency, cost etc. The rigorous safety analysis carried out for the subsea production equipment is then explained in depth. The paper continues with a technical discussion of the main features specific to the SpoolTreemore » design and the Garden Banks 388 field development. Issues discussed include the SpoolTree itself, BOP Adapter Plate (for control during installation, workover and production), Tubing Hanger and pressure barrier design, debris cap design, downhole communication (SCSSV, chemical injection, pressure and temperature) ROV intervention, template wellbay insert design and other relevant issues. The use of computer based 3-D modelling tool is also briefly described. The experience and results described in this paper have direct application to numerous subsea development prospects worldwide, particularly in deep water. In addition, the ``system development`` aspect of the project is relevant to most marine equipment development projects. This includes the use of safety analysis techniques, 3-D computer modelling tools and clearly defined engineering procedures. A full account of the final design configuration of the SpoolTree system is given in the paper. A summary of the experience gained during the extensive testing at the factory and during the template integration tests is also provided.« less

On Tree-Based Phylogenetic Networks.

PubMed

Zhang, Louxin

2016-07-01

A large class of phylogenetic networks can be obtained from trees by the addition of horizontal edges between the tree edges. These networks are called tree-based networks. We present a simple necessary and sufficient condition for tree-based networks and prove that a universal tree-based network exists for any number of taxa that contains as its base every phylogenetic tree on the same set of taxa. This answers two problems posted by Francis and Steel recently. A byproduct is a computer program for generating random binary phylogenetic networks under the uniform distribution model.

Technical aspects of virtual liver resection planning.

PubMed

Glombitza, G; Lamadé, W; Demiris, A M; Göpfert, M R; Mayer, A; Bahner, M L; Meinzer, H P; Richter, G; Lehnert, T; Herfarth, C

1998-01-01

Operability of a liver tumor is depending on its three dimensional relation to the intrahepatic vascular trees which define autonomously functioning liver (sub-)segments. Precise operation planning is complicated by anatomic variability, distortion of the vascular trees by the tumor or preceding liver resections. Because of the missing possibility to track the deformation of the liver during the operation an integration of the resection planning system into an intra-operative navigation system is not feasible. So the main task of an operation planning system in this domain is a quantifiable patient selection by exact prediction of post-operative liver function and a quantifiable resection proposal. The system quantifies the organ structures and resection volumes by means of absolute and relative values. It defines resection planes depending on security margins and the vascular trees and presents the data in visualized form as a 3D movie. The new 3D operation planning system offers quantifiable liver resection proposals based on individualized liver anatomy. The results are visualized in digital movies as well as in quantitative reports.

Mainstreaming conservation agriculture in Malawi: Knowledge gaps and institutional barriers.

PubMed

Dougill, Andrew J; Whitfield, Stephen; Stringer, Lindsay C; Vincent, Katharine; Wood, Benjamin T; Chinseu, Edna L; Steward, Peter; Mkwambisi, David D

2017-06-15

Conservation agriculture (CA) practices of reduced soil tillage, permanent organic soil coverage and intercropping/crop rotation, are being advocated globally, based on perceived benefits for crop yields, soil carbon storage, weed suppression, reduced soil erosion and improved soil water retention. However, some have questioned their efficacy due to uncertainty around the performance and trade-offs associated with CA practices, and their compatibility with the diverse livelihood strategies and varied agro-ecological conditions across African smallholder systems. This paper assesses the role of key institutions in Malawi in shaping pathways towards more sustainable land management based on CA by outlining their impact on national policy-making and the design and implementation of agricultural development projects. It draws on interviews at national, district and project levels and a multi-stakeholder workshop that mapped the institutional landscape of decision-making for agricultural land management practices. Findings identify knowledge gaps and institutional barriers that influence land management decision-making and constrain CA uptake. We use our findings to set out an integrated roadmap of research needs and policy options aimed at supporting CA as a route to enhanced sustainable land management in Malawi. Findings offer lessons that can inform design, planning and implementation of CA projects, and identify the multi-level institutional support structures required for mainstreaming sustainable land management in sub-Saharan Africa. Copyright © 2016 Elsevier Ltd. All rights reserved.

Interactive tree of life (iTOL) v3: an online tool for the display and annotation of phylogenetic and other trees.

PubMed

Letunic, Ivica; Bork, Peer

2016-07-08

Interactive Tree Of Life (http://itol.embl.de) is a web-based tool for the display, manipulation and annotation of phylogenetic trees. It is freely available and open to everyone. The current version was completely redesigned and rewritten, utilizing current web technologies for speedy and streamlined processing. Numerous new features were introduced and several new data types are now supported. Trees with up to 100,000 leaves can now be efficiently displayed. Full interactive control over precise positioning of various annotation features and an unlimited number of datasets allow the easy creation of complex tree visualizations. iTOL 3 is the first tool which supports direct visualization of the recently proposed phylogenetic placements format. Finally, iTOL's account system has been redesigned to simplify the management of trees in user-defined workspaces and projects, as it is heavily used and currently handles already more than 500,000 trees from more than 10,000 individual users. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Benefit-based tree valuation

Treesearch

E.G. McPherson

2007-01-01

Benefit-based tree valuation provides alternative estimates of the fair and reasonable value of trees while illustrating the relative contribution of different benefit types. This study compared estimates of tree value obtained using cost- and benefit-based approaches. The cost-based approach used the Council of Landscape and Tree Appraisers trunk formula method, and...

Ontology based decision system for breast cancer diagnosis

NASA Astrophysics Data System (ADS)

Trabelsi Ben Ameur, Soumaya; Cloppet, Florence; Wendling, Laurent; Sellami, Dorra

2018-04-01

In this paper, we focus on analysis and diagnosis of breast masses inspired by expert concepts and rules. Accordingly, a Bag of Words is built based on the ontology of breast cancer diagnosis, accurately described in the Breast Imaging Reporting and Data System. To fill the gap between low level knowledge and expert concepts, a semantic annotation is developed using a machine learning tool. Then, breast masses are classified into benign or malignant according to expert rules implicitly modeled with a set of classifiers (KNN, ANN, SVM and Decision Tree). This semantic context of analysis offers a frame where we can include external factors and other meta-knowledge such as patient risk factors as well as exploiting more than one modality. Based on MRI and DECEDM modalities, our developed system leads a recognition rate of 99.7% with Decision Tree where an improvement of 24.7 % is obtained owing to semantic analysis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bryngelson, R.H.

Describes installation of 3 satellite subsea trees in 500 ft of water from a semisubmersible drilling rig. These wet, diver-assist trees are part of Phillips Petroleum's early development and production program (EDPP) for the Espoir field offshore Ivory Coast, with plans calling for 5 satellite wells with downhole completion equipment and subsea production trees. Diagram shows how a converted jackup, Dan Duke, supports equipment to handle production from subsea wells. Table gives time breakdown of subsea tree installation. Before mobilizing the subsea trees, control system, and tubulars to the rig, a study of deck layout, payloads, and traffic patterns wasmore » performed. Concludes that, based on experience in this project and the cost differences between purchase and installation costs, final success is 90% dependent on informed and trained field personnel after engineering, design, and manufacturing; attention to installation procedures and training of field and operational personnel are as critical or more critical than design changes to equipment; and selection of a supplier for high technology equipment, based on a low bid alone, may not translate into lower installation costs.« less

Extended GTST-MLD for aerospace system safety analysis.

PubMed

Guo, Chiming; Gong, Shiyu; Tan, Lin; Guo, Bo

2012-06-01

The hazards caused by complex interactions in the aerospace system have become a problem that urgently needs to be settled. This article introduces a method for aerospace system hazard interaction identification based on extended GTST-MLD (goal tree-success tree-master logic diagram) during the design stage. GTST-MLD is a functional modeling framework with a simple architecture. Ontology is used to extend the ability of system interaction description in GTST-MLD by adding the system design knowledge and the past accident experience. From the level of functionality and equipment, respectively, this approach can help the technician detect potential hazard interactions. Finally, a case is used to show the method. © 2011 Society for Risk Analysis.

Method for 3D noncontact measurements of cut trees package area

NASA Astrophysics Data System (ADS)

Knyaz, Vladimir A.; Vizilter, Yuri V.

2001-02-01

Progress in imaging sensors and computers create the background for numerous 3D imaging application for wide variety of manufacturing activity. Many demands for automated precise measurements are in wood branch of industry. One of them is the accurate volume definition for cut trees carried on the truck. The key point for volume estimation is determination of the front area of the cut tree package. To eliminate slow and inaccurate manual measurements being now in practice the experimental system for automated non-contact wood measurements is developed. The system includes two non-metric CCD video cameras, PC as central processing unit, frame grabbers and original software for image processing and 3D measurements. The proposed method of measurement is based on capturing the stereo pair of front of trees package and performing the image orthotranformation into the front plane. This technique allows to process transformed image for circle shapes recognition and calculating their area. The metric characteristics of the system are provided by special camera calibration procedure. The paper presents the developed method of 3D measurements, describes the hardware used for image acquisition and the software realized the developed algorithms, gives the productivity and precision characteristics of the system.

Modular techniques for dynamic fault-tree analysis

NASA Technical Reports Server (NTRS)

Patterson-Hine, F. A.; Dugan, Joanne B.

1992-01-01

It is noted that current approaches used to assess the dependability of complex systems such as Space Station Freedom and the Air Traffic Control System are incapable of handling the size and complexity of these highly integrated designs. A novel technique for modeling such systems which is built upon current techniques in Markov theory and combinatorial analysis is described. It enables the development of a hierarchical representation of system behavior which is more flexible than either technique alone. A solution strategy which is based on an object-oriented approach to model representation and evaluation is discussed. The technique is virtually transparent to the user since the fault tree models can be built graphically and the objects defined automatically. The tree modularization procedure allows the two model types, Markov and combinatoric, to coexist and does not require that the entire fault tree be translated to a Markov chain for evaluation. This effectively reduces the size of the Markov chain required and enables solutions with less truncation, making analysis of longer mission times possible. Using the fault-tolerant parallel processor as an example, a model is built and solved for a specific mission scenario and the solution approach is illustrated in detail.

Proposed Hydrodynamic Model Increases the Ability of Land-Surface Models to Capture Intra-Daily Dynamics of Transpiration and Canopy Structure Effects

NASA Astrophysics Data System (ADS)

Matheny, A. M.; Bohrer, G.; Mirfenderesgi, G.; Schafer, K. V.; Ivanov, V. Y.

2014-12-01

Hydraulic limitations are known to control transpiration in forest ecosystems when the soil is drying or when the vapor pressure deficit between the air and stomata is very large, but they can also impact stomatal apertures under conditions of adequate soil moisture and lower evaporative demand. We use the NACP dataset of latent heat flux measurements and model observations for multiple sites and models to demonstrate models' difficulties in capturing intra-daily hysteresis. We hypothesize that this is a result of un-resolved afternoon stomata closure due to hydrodynamic stresses. The current formulations for stomatal conductance and the empirical coupling between stomatal conductance and soil moisture used by these models does not resolve the hydrodynamic process of water movement from the soil to the leaves. This approach does not take advantage of advances in our understanding of water flow and storage in the trees, or of tree and canopy structure. A more thorough representation of the tree-hydrodynamic processes could potentially remedy this significant source of model error. In a forest plot at the University of Michigan Biological Station, we use measurements of sap flux and leaf water potential to demonstrate that trees of similar type - late successional deciduous trees - have very different hydrodynamic strategies that lead to differences in their temporal patterns of stomatal conductance and thus hysteretic cycles of transpiration. These differences will lead to large differences in conductance and water use based on the species composition of the forest. We also demonstrate that the size and shape of the tree branching system leads to differences in extent of hydrodynamic stress, which may change the forest respiration patterns as the forest grows and ages. We propose a framework to resolve tree hydrodynamics in global and regional models based on the Finite-Elements Tree-Crown Hydrodynamics model (FETCH) -a hydrodynamic model that can resolve the fast dynamics of stomatal conductance. FETCH simulates water flow through a tree as a system of porous media conduits and calculates the amount of hydraulic limitation to stomatal conductance, given the atmospheric and biological variables from the global model, and could replace the current empirical formulation for stomatal adjustment based on soil moisture.

[Development of whole process quality control and management system of traditional Chinese medicine decoction pieces based on traditional Chinese medicine quality tree].

PubMed

Yu, Wen-Kang; Dong, Ling; Pei, Wen-Xuan; Sun, Zhi-Rong; Dai, Jun-Dong; Wang, Yun

2017-12-01

The whole process quality control and management of traditional Chinese medicine (TCM) decoction pieces is a system engineering, involving the base environment, seeds and seedlings, harvesting, processing and other multiple steps, so the accurate identification of factors in TCM production process that may induce the quality risk, as well as reasonable quality control measures are very important. At present, the concept of quality risk is mainly concentrated in the aspects of management and regulations, etc. There is no comprehensive analysis on possible risks in the quality control process of TCM decoction pieces, or analysis summary of effective quality control schemes. A whole process quality control and management system for TCM decoction pieces based on TCM quality tree was proposed in this study. This system effectively combined the process analysis method of TCM quality tree with the quality risk management, and can help managers to make real-time decisions while realizing the whole process quality control of TCM. By providing personalized web interface, this system can realize user-oriented information feedback, and was convenient for users to predict, evaluate and control the quality of TCM. In the application process, the whole process quality control and management system of the TCM decoction pieces can identify the related quality factors such as base environment, cultivation and pieces processing, extend and modify the existing scientific workflow according to their own production conditions, and provide different enterprises with their own quality systems, to achieve the personalized service. As a new quality management model, this paper can provide reference for improving the quality of Chinese medicine production and quality standardization. Copyright© by the Chinese Pharmaceutical Association.

Transpiration and root development of urban trees in structural soil stormwater reservoirs.

PubMed

Bartens, Julia; Day, Susan D; Harris, J Roger; Wynn, Theresa M; Dove, Joseph E

2009-10-01

Stormwater management that relies on ecosystem processes, such as tree canopy interception and rhizosphere biology, can be difficult to achieve in built environments because urban land is costly and urban soil inhospitable to vegetation. Yet such systems offer a potentially valuable tool for achieving both sustainable urban forests and stormwater management. We evaluated tree water uptake and root distribution in a novel stormwater mitigation facility that integrates trees directly into detention reservoirs under pavement. The system relies on structural soils: highly porous engineered mixes designed to support tree root growth and pavement. To evaluate tree performance under the peculiar conditions of such a stormwater detention reservoir (i.e., periodically inundated), we grew green ash (Fraxinus pennsylvanica Marsh.) and swamp white oak (Quercus bicolor Willd.) in either CUSoil or a Carolina Stalite-based mix subjected to three simulated below-system infiltration rates for two growing seasons. Infiltration rate affected both transpiration and rooting depth. In a factorial experiment with ash, rooting depth always increased with infiltration rate for Stalite, but this relation was less consistent for CUSoil. Slow-drainage rates reduced transpiration and restricted rooting depth for both species and soils, and trunk growth was restricted for oak, which grew the most in moderate infiltration. Transpiration rates under slow infiltration were 55% (oak) and 70% (ash) of the most rapidly transpiring treatment (moderate for oak and rapid for ash). We conclude this system is feasible and provides another tool to address runoff that integrates the function of urban green spaces with other urban needs.

Interpretable Categorization of Heterogeneous Time Series Data

NASA Technical Reports Server (NTRS)

Lee, Ritchie; Kochenderfer, Mykel J.; Mengshoel, Ole J.; Silbermann, Joshua

2017-01-01

We analyze data from simulated aircraft encounters to validate and inform the development of a prototype aircraft collision avoidance system. The high-dimensional and heterogeneous time series dataset is analyzed to discover properties of near mid-air collisions (NMACs) and categorize the NMAC encounters. Domain experts use these properties to better organize and understand NMAC occurrences. Existing solutions either are not capable of handling high-dimensional and heterogeneous time series datasets or do not provide explanations that are interpretable by a domain expert. The latter is critical to the acceptance and deployment of safety-critical systems. To address this gap, we propose grammar-based decision trees along with a learning algorithm. Our approach extends decision trees with a grammar framework for classifying heterogeneous time series data. A context-free grammar is used to derive decision expressions that are interpretable, application-specific, and support heterogeneous data types. In addition to classification, we show how grammar-based decision trees can also be used for categorization, which is a combination of clustering and generating interpretable explanations for each cluster. We apply grammar-based decision trees to a simulated aircraft encounter dataset and evaluate the performance of four variants of our learning algorithm. The best algorithm is used to analyze and categorize near mid-air collisions in the aircraft encounter dataset. We describe each discovered category in detail and discuss its relevance to aircraft collision avoidance.

Tree growth rates in an Amazonian evergreen forest: seasonal patterns and correlations with leaf phenology

NASA Astrophysics Data System (ADS)

Wu, J.; Silva Campos, K.; Prohaska, N.; Ferreira, M. L.; Nelson, B. W.; Saleska, S. R.; da Silva, R.

2014-12-01

Metabolism and phenology of tropical forests significantly influence global dynamics of climate, carbon and water. However, there is still lack of mechanistic understanding of the controls on tropical forest metabolism, particularly at individual tree level. In this study, we are interested in investigating (1) what is the seasonal pattern of woody growth for tropical trees and (2) what is the mechanistic controls onwoody growth at individual level?To explore the above questions,we use two data sources from an evergreen tropical forest KM67 site (near Santarem, Brazil). They are: (1) image time series from a tower mounted RGB imaging system, with images recordedin10 minutes interval since October 2013.Images near local noon homogeneous diffuse lighting were selectedfor leaf phenologymonitoring; (2) ground based bi-weekly biometry survey (via dendrometry band technique) for 25 trees from random sampling since September 2013. 12 among 25 trees are within the tower mounted camera image view. Our preliminary resultsdemonstrate that 20 trees among 25 trees surveyed significantly increase woody growth (or "green up") in dry season. Our results also find thatamong those 20 trees, 12 trees reaches the maximum woody increment rate in late dry season with a mean DBH (Diameter at Breast Height) around 30 cm,while 8 trees reaching the maximum in the middle of wet season, with a mean DBH around 90 cm. This study,though limited in the sample size, mightprovide another line of evidence that Amazon rainforests "green up" in dry season. As for mechanistic controls on tropical tree woody control, we hypothesize both climate and leaf phenology control individual woody growth. We would like to link both camera based leaf phenology and climate data in the next to explorethe reason as to the pattern found in this study that bigger trees might have different seasonal growth pattern as smaller trees.

A review on machine learning principles for multi-view biological data integration.

PubMed

Li, Yifeng; Wu, Fang-Xiang; Ngom, Alioune

2018-03-01

Driven by high-throughput sequencing techniques, modern genomic and clinical studies are in a strong need of integrative machine learning models for better use of vast volumes of heterogeneous information in the deep understanding of biological systems and the development of predictive models. How data from multiple sources (called multi-view data) are incorporated in a learning system is a key step for successful analysis. In this article, we provide a comprehensive review on omics and clinical data integration techniques, from a machine learning perspective, for various analyses such as prediction, clustering, dimension reduction and association. We shall show that Bayesian models are able to use prior information and model measurements with various distributions; tree-based methods can either build a tree with all features or collectively make a final decision based on trees learned from each view; kernel methods fuse the similarity matrices learned from individual views together for a final similarity matrix or learning model; network-based fusion methods are capable of inferring direct and indirect associations in a heterogeneous network; matrix factorization models have potential to learn interactions among features from different views; and a range of deep neural networks can be integrated in multi-modal learning for capturing the complex mechanism of biological systems.

Nonbinary Tree-Based Phylogenetic Networks.

PubMed

Jetten, Laura; van Iersel, Leo

2018-01-01

Rooted phylogenetic networks are used to describe evolutionary histories that contain non-treelike evolutionary events such as hybridization and horizontal gene transfer. In some cases, such histories can be described by a phylogenetic base-tree with additional linking arcs, which can, for example, represent gene transfer events. Such phylogenetic networks are called tree-based. Here, we consider two possible generalizations of this concept to nonbinary networks, which we call tree-based and strictly-tree-based nonbinary phylogenetic networks. We give simple graph-theoretic characterizations of tree-based and strictly-tree-based nonbinary phylogenetic networks. Moreover, we show for each of these two classes that it can be decided in polynomial time whether a given network is contained in the class. Our approach also provides a new view on tree-based binary phylogenetic networks. Finally, we discuss two examples of nonbinary phylogenetic networks in biology and show how our results can be applied to them.

Review: Evaluation of Foot-and-Mouth Disease Control Using Fault Tree Analysis.

PubMed

Isoda, N; Kadohira, M; Sekiguchi, S; Schuppers, M; Stärk, K D C

2015-06-01

An outbreak of foot-and-mouth disease (FMD) causes huge economic losses and animal welfare problems. Although much can be learnt from past FMD outbreaks, several countries are not satisfied with their degree of contingency planning and aiming at more assurance that their control measures will be effective. The purpose of the present article was to develop a generic fault tree framework for the control of an FMD outbreak as a basis for systematic improvement and refinement of control activities and general preparedness. Fault trees are typically used in engineering to document pathways that can lead to an undesired event, that is, ineffective FMD control. The fault tree method allows risk managers to identify immature parts of the control system and to analyse the events or steps that will most probably delay rapid and effective disease control during a real outbreak. The present developed fault tree is generic and can be tailored to fit the specific needs of countries. For instance, the specific fault tree for the 2001 FMD outbreak in the UK was refined based on control weaknesses discussed in peer-reviewed articles. Furthermore, the specific fault tree based on the 2001 outbreak was applied to the subsequent FMD outbreak in 2007 to assess the refinement of control measures following the earlier, major outbreak. The FMD fault tree can assist risk managers to develop more refined and adequate control activities against FMD outbreaks and to find optimum strategies for rapid control. Further application using the current tree will be one of the basic measures for FMD control worldwide. © 2013 Blackwell Verlag GmbH.

DG TO FT - AUTOMATIC TRANSLATION OF DIGRAPH TO FAULT TREE MODELS

NASA Technical Reports Server (NTRS)

Iverson, D. L.

1994-01-01

Fault tree and digraph models are frequently used for system failure analysis. Both types of models represent a failure space view of the system using AND and OR nodes in a directed graph structure. Each model has its advantages. While digraphs can be derived in a fairly straightforward manner from system schematics and knowledge about component failure modes and system design, fault tree structure allows for fast processing using efficient techniques developed for tree data structures. The similarities between digraphs and fault trees permits the information encoded in the digraph to be translated into a logically equivalent fault tree. The DG TO FT translation tool will automatically translate digraph models, including those with loops or cycles, into fault tree models that have the same minimum cut set solutions as the input digraph. This tool could be useful, for example, if some parts of a system have been modeled using digraphs and others using fault trees. The digraphs could be translated and incorporated into the fault trees, allowing them to be analyzed using a number of powerful fault tree processing codes, such as cut set and quantitative solution codes. A cut set for a given node is a group of failure events that will cause the failure of the node. A minimum cut set for a node is any cut set that, if any of the failures in the set were to be removed, the occurrence of the other failures in the set will not cause the failure of the event represented by the node. Cut sets calculations can be used to find dependencies, weak links, and vital system components whose failures would cause serious systems failure. The DG TO FT translation system reads in a digraph with each node listed as a separate object in the input file. The user specifies a terminal node for the digraph that will be used as the top node of the resulting fault tree. A fault tree basic event node representing the failure of that digraph node is created and becomes a child of the terminal root node. A subtree is created for each of the inputs to the digraph terminal node and the root of those subtrees are added as children of the top node of the fault tree. Every node in the digraph upstream of the terminal node will be visited and converted. During the conversion process, the algorithm keeps track of the path from the digraph terminal node to the current digraph node. If a node is visited twice, then the program has found a cycle in the digraph. This cycle is broken by finding the minimal cut sets of the twice visited digraph node and forming those cut sets into subtrees. Another implementation of the algorithm resolves loops by building a subtree based on the digraph minimal cut sets calculation. It does not reduce the subtree to minimal cut set form. This second implementation produces larger fault trees, but runs much faster than the version using minimal cut sets since it does not spend time reducing the subtrees to minimal cut sets. The fault trees produced by DG TO FT will contain OR gates, AND gates, Basic Event nodes, and NOP gates. The results of a translation can be output as a text object description of the fault tree similar to the text digraph input format. The translator can also output a LISP language formatted file and an augmented LISP file which can be used by the FTDS (ARC-13019) diagnosis system, available from COSMIC, which performs diagnostic reasoning using the fault tree as a knowledge base. DG TO FT is written in C-language to be machine independent. It has been successfully implemented on a Sun running SunOS, a DECstation running ULTRIX, a Macintosh running System 7, and a DEC VAX running VMS. The RAM requirement varies with the size of the models. DG TO FT is available in UNIX tar format on a .25 inch streaming magnetic tape cartridge (standard distribution) or on a 3.5 inch diskette. It is also available on a 3.5 inch Macintosh format diskette or on a 9-track 1600 BPI magnetic tape in DEC VAX FILES-11 format. Sample input and sample output are provided on the distribution medium. An electronic copy of the documentation in Macintosh Microsoft Word format is provided on the distribution medium. DG TO FT was developed in 1992. Sun, and SunOS are trademarks of Sun Microsystems, Inc. DECstation, ULTRIX, VAX, and VMS are trademarks of Digital Equipment Corporation. UNIX is a registered trademark of AT&T Bell Laboratories. Macintosh is a registered trademark of Apple Computer, Inc. System 7 is a trademark of Apple Computers Inc. Microsoft Word is a trademark of Microsoft Corporation.

Resolving Evolutionary Relationships in Closely Related Species with Whole-Genome Sequencing Data

PubMed Central

Nater, Alexander; Burri, Reto; Kawakami, Takeshi; Smeds, Linnéa; Ellegren, Hans

2015-01-01

Using genetic data to resolve the evolutionary relationships of species is of major interest in evolutionary and systematic biology. However, reconstructing the sequence of speciation events, the so-called species tree, in closely related and potentially hybridizing species is very challenging. Processes such as incomplete lineage sorting and interspecific gene flow result in local gene genealogies that differ in their topology from the species tree, and analyses of few loci with a single sequence per species are likely to produce conflicting or even misleading results. To study these phenomena on a full phylogenomic scale, we use whole-genome sequence data from 200 individuals of four black-and-white flycatcher species with so far unresolved phylogenetic relationships to infer gene tree topologies and visualize genome-wide patterns of gene tree incongruence. Using phylogenetic analysis in nonoverlapping 10-kb windows, we show that gene tree topologies are extremely diverse and change on a very small physical scale. Moreover, we find strong evidence for gene flow among flycatcher species, with distinct patterns of reduced introgression on the Z chromosome. To resolve species relationships on the background of widespread gene tree incongruence, we used four complementary coalescent-based methods for species tree reconstruction, including complex modeling approaches that incorporate post-divergence gene flow among species. This allowed us to infer the most likely species tree with high confidence. Based on this finding, we show that regions of reduced effective population size, which have been suggested as particularly useful for species tree inference, can produce positively misleading species tree topologies. Our findings disclose the pitfalls of using loci potentially under selection as phylogenetic markers and highlight the potential of modeling approaches to disentangle species relationships in systems with large effective population sizes and post-divergence gene flow. PMID:26187295

Cloud Detection from Satellite Imagery: A Comparison of Expert-Generated and Automatically-Generated Decision Trees

NASA Technical Reports Server (NTRS)

Shiffman, Smadar

2004-01-01

Automated cloud detection and tracking is an important step in assessing global climate change via remote sensing. Cloud masks, which indicate whether individual pixels depict clouds, are included in many of the data products that are based on data acquired on- board earth satellites. Many cloud-mask algorithms have the form of decision trees, which employ sequential tests that scientists designed based on empirical astrophysics studies and astrophysics simulations. Limitations of existing cloud masks restrict our ability to accurately track changes in cloud patterns over time. In this study we explored the potential benefits of automatically-learned decision trees for detecting clouds from images acquired using the Advanced Very High Resolution Radiometer (AVHRR) instrument on board the NOAA-14 weather satellite of the National Oceanic and Atmospheric Administration. We constructed three decision trees for a sample of 8km-daily AVHRR data from 2000 using a decision-tree learning procedure provided within MATLAB(R), and compared the accuracy of the decision trees to the accuracy of the cloud mask. We used ground observations collected by the National Aeronautics and Space Administration Clouds and the Earth s Radiant Energy Systems S COOL project as the gold standard. For the sample data, the accuracy of automatically learned decision trees was greater than the accuracy of the cloud masks included in the AVHRR data product.

Dendrogeomorphic analysis of flash floods in a small ungauged mountain catchment (Central Spain)

NASA Astrophysics Data System (ADS)

Ruiz-Villanueva, Virginia; Díez-Herrero, Andrés; Stoffel, Markus; Bollschweiler, Michelle; Bodoque, José M.; Ballesteros, Juan A.

2010-06-01

Flash floods represent one of the most significant natural hazards with serious death tolls and economic damage at a worldwide level in general and in Mediterranean mountain catchments in particular. In these environments, systematic data is often lacking and analyses have to be based on alternative approaches such as dendrogeomorphology. In this study, we focus on the identification of flash floods based on growth disturbances (GD) observed in 98 heavily affected Mediterranean pine trees ( Pinus pinaster Ait.) located in or next to the torrential channel of the Pelayo River in the Spanish Central System. Flash floods are quite common in this catchment and are triggered by heavy storms, with high discharge and debris transport rates favoured by high stream gradients. Comparison of the anomalies in tree morphology and the position of the trees in the channel showed that the intensity of the disturbance clearly depends on geomorphology. The dating of past flash flood events was based on the number and intensity of GD observed in the tree-ring series and on the spatial distribution of affected trees along the torrent, thus allowing seven flash flood events during the last 50 years to be dated, namely in 1963, 1966, 1973, 1976, 1996, 2000, and 2005.

Dendrogeomorphic analysis of Flash Floods in a small ungauged mountain catchment (Central Spain)

NASA Astrophysics Data System (ADS)

Ruiz-Villanueva, Virginia; Díez-Herrero, Andrés.; Stoffel, Markus; Bollschweiler, Michelle; María Bodoque, José; Ballesteros, Juan Antonio

2010-05-01

Flash floods represent one of the most significant natural hazards with serious death tolls and economic damage at a worldwide level in general and in Mediterranean mountain catchments in particular. In these environments, systematic data is often lacking and analyses have to be based on alternative approaches such as dendrogeomorphology. In this study, we focus on the identification of flash floods based on growth disturbances (GD) observed in 98 heavily affected Mediterranean pine trees (Pinus pinaster Ait.) located in or next to the torrential channel of the Pelayo River in the Spanish Central System. Flash floods are quite common in this catchment and are triggered by heavy storms, with high discharge and debris transport rates favoured by high stream gradients. Comparison of the anomalies in tree morphology and the position of the trees in the channel showed that the intensity of the disturbance clearly depends on geomorphology. The dating of past flash-flood events was based on the number and intensity of GD observed in the tree-ring series, and on the spatial distribution of affected trees along the torrent, thus allowing seven flash-flood events during the last ~50 years to be dated, namely in 1963, 1966, 1973, 1976, 1996, 2000, and 2005.

A fast bottom-up algorithm for computing the cut sets of noncoherent fault trees

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corynen, G.C.

1987-11-01

An efficient procedure for finding the cut sets of large fault trees has been developed. Designed to address coherent or noncoherent systems, dependent events, shared or common-cause events, the method - called SHORTCUT - is based on a fast algorithm for transforming a noncoherent tree into a quasi-coherent tree (COHERE), and on a new algorithm for reducing cut sets (SUBSET). To assure sufficient clarity and precision, the procedure is discussed in the language of simple sets, which is also developed in this report. Although the new method has not yet been fully implemented on the computer, we report theoretical worst-casemore » estimates of its computational complexity. 12 refs., 10 figs.« less

Metalized polyethylene mulch to repel Asian citrus psyllid, slow spread of huanglongbing and improve growth of new citrus plantings.

PubMed

Croxton, Scott D; Stansly, Philip A

2014-02-01

Greening or huanglongbing (HLB) is a debilitating disease of citrus caused by Candidatus Liberibactor asiaticus and transmitted by the Asian citrus psyllid (ACP), Diaphorina citri. HLB now occurs worldwide in all major citrus growing regions except the Mediterranean and Australia. Management relies principally on insecticidal control of the ACP vector, but is insufficient, even for young trees which are most susceptible to the disease. We tested the ability of metalized polyethylene mulch to repel adult ACP as well as effects on incidence of HLB and early tree growth. Metalized mulch significantly reduced ACP populations and HLB incidence compared to whiteface mulch or bare ground. In addition, metalized mulch, together with the associated drip irrigation and fertigation system, increased soil moisture, reduced weed pressure, and increased tree growth rate. Metalized mulch slows spread of ACP and therefore HLB pressure on young citrus trees. Metalized mulch can thereby augment current control measures for young trees based primarily on systemic insecticides. Additional costs could be compensated for by increased tree growth rate which would shorten time to crop profitability. These advantages make a compelling case for large-scale trials using metalized mulch in young citrus plantings threatened by HLB. © 2013 Society of Chemical Industry.

The prediction of breast cancer biopsy outcomes using two CAD approaches that both emphasize an intelligible decision process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elter, M.; Schulz-Wendtland, R.; Wittenberg, T.

2007-11-15

Mammography is the most effective method for breast cancer screening available today. However, the low positive predictive value of breast biopsy resulting from mammogram interpretation leads to approximately 70% unnecessary biopsies with benign outcomes. To reduce the high number of unnecessary breast biopsies, several computer-aided diagnosis (CAD) systems have been proposed in the last several years. These systems help physicians in their decision to perform a breast biopsy on a suspicious lesion seen in a mammogram or to perform a short term follow-up examination instead. We present two novel CAD approaches that both emphasize an intelligible decision process to predictmore » breast biopsy outcomes from BI-RADS findings. An intelligible reasoning process is an important requirement for the acceptance of CAD systems by physicians. The first approach induces a global model based on decison-tree learning. The second approach is based on case-based reasoning and applies an entropic similarity measure. We have evaluated the performance of both CAD approaches on two large publicly available mammography reference databases using receiver operating characteristic (ROC) analysis, bootstrap sampling, and the ANOVA statistical significance test. Both approaches outperform the diagnosis decisions of the physicians. Hence, both systems have the potential to reduce the number of unnecessary breast biopsies in clinical practice. A comparison of the performance of the proposed decision tree and CBR approaches with a state of the art approach based on artificial neural networks (ANN) shows that the CBR approach performs slightly better than the ANN approach, which in turn results in slightly better performance than the decision-tree approach. The differences are statistically significant (p value <0.001). On 2100 masses extracted from the DDSM database, the CRB approach for example resulted in an area under the ROC curve of A(z)=0.89{+-}0.01, the decision-tree approach in A(z)=0.87{+-}0.01, and the ANN approach in A(z)=0.88{+-}0.01.« less

Impact of Organic Amendments on Global Warming Potential of Diversified Tropical Rice Rotation Systems

NASA Astrophysics Data System (ADS)

Janz, B.; Weller, S.; Kraus, D.; Wassmann, R.; Butterbach-Bahl, K.; Ralf, K.

2017-12-01

Paddy rice cultivation is increasingly challenged by irrigation water scarcity, which is forcing farmers to change traditional rice cultivation from flooded double-rice systems to the introduction of well-aerated upland crops during dry season. Emissions of methane (CH4) are expected to decrease, while there is a risk of increasing emissions of nitrous oxide (N2O) and decreasing soil organic carbon (SOC) stocks through volatilization in the form of carbon dioxide (CO2). We present a unique dataset of long-term continuous greenhouse gas emission measurements (CH4 and N2O) in the Philippines to assess global warming potentials (GWP) of diversified rice crop rotations including different field management practices such as straw residue application and legume intercropping. Since 2012, more than four years of CH4 and N2O emissions in double-rice cropping (R-R) and paddy rice rotations diversified with either maize (R-M) or aerobic rice (R-A) during dry season have been collected. Introduction of upland crops reduced irrigation water use and CH4 emissions by 66-81% and 95-99%, respectively. Although dry season N2O emissions increased twice- to threefold in the diversified systems, the strong reduction of CH4 led to a significantly lower annual GWP (CH4 + N2O) as compared to the traditional R-R system. Diversified crop management practices were first implemented during land-preparation for dry season 2015 where i) 6 t/ha rice straw was returned to the field and ii) mungbean was grown as a cover-crop between dry and wet season in addition to rice straw application. The input of organic material (straw and mungbean) led to higher substrate availability for methanogens during the following season. Therefore, GWP was 9-39% higher following straw incorporation than the control treatment. This increase was mainly driven by additional CH4 emissions. Even more, mungbean intercropping further increased GWPs, whereby the increment was highest in R-R rotation (88%) and lowest in R-M rotation (55%), with annual emissions of 11.8 and 5.6 t CO2 eq. ha-1, respectively. Nevertheless, regarding a future expansion of lowland-upland rotations due to water scarcity in SE Asia it can be expected that input of crop residues can counteract the SOC loss that is likely associated with the shift to more aerated soil conditions under upland crops.

Implementation of a Goal-Based Systems Engineering Process Using the Systems Modeling Language (SysML)

NASA Technical Reports Server (NTRS)

Patterson, Jonathan D.; Breckenridge, Jonathan T.; Johnson, Stephen B.

2013-01-01

Building upon the purpose, theoretical approach, and use of a Goal-Function Tree (GFT) being presented by Dr. Stephen B. Johnson, described in a related Infotech 2013 ISHM abstract titled "Goal-Function Tree Modeling for Systems Engineering and Fault Management", this paper will describe the core framework used to implement the GFTbased systems engineering process using the Systems Modeling Language (SysML). These two papers are ideally accepted and presented together in the same Infotech session. Statement of problem: SysML, as a tool, is currently not capable of implementing the theoretical approach described within the "Goal-Function Tree Modeling for Systems Engineering and Fault Management" paper cited above. More generally, SysML's current capabilities to model functional decompositions in the rigorous manner required in the GFT approach are limited. The GFT is a new Model-Based Systems Engineering (MBSE) approach to the development of goals and requirements, functions, and its linkage to design. As a growing standard for systems engineering, it is important to develop methods to implement GFT in SysML. Proposed Method of Solution: Many of the central concepts of the SysML language are needed to implement a GFT for large complex systems. In the implementation of those central concepts, the following will be described in detail: changes to the nominal SysML process, model view definitions and examples, diagram definitions and examples, and detailed SysML construct and stereotype definitions.

Performance of Case-Based Reasoning Retrieval Using Classification Based on Associations versus Jcolibri and FreeCBR: A Further Validation Study

NASA Astrophysics Data System (ADS)

Aljuboori, Ahmed S.; Coenen, Frans; Nsaif, Mohammed; Parsons, David J.

2018-05-01

Case-Based Reasoning (CBR) plays a major role in expert system research. However, a critical problem can be met when a CBR system retrieves incorrect cases. Class Association Rules (CARs) have been utilized to offer a potential solution in a previous work. The aim of this paper was to perform further validation of Case-Based Reasoning using a Classification based on Association Rules (CBRAR) to enhance the performance of Similarity Based Retrieval (SBR). The CBRAR strategy uses a classed frequent pattern tree algorithm (FP-CAR) in order to disambiguate wrongly retrieved cases in CBR. The research reported in this paper makes contributions to both fields of CBR and Association Rules Mining (ARM) in that full target cases can be extracted from the FP-CAR algorithm without invoking P-trees and union operations. The dataset used in this paper provided more efficient results when the SBR retrieves unrelated answers. The accuracy of the proposed CBRAR system outperforms the results obtained by existing CBR tools such as Jcolibri and FreeCBR.

Boolean logic tree of graphene-based chemical system for molecular computation and intelligent molecular search query.

PubMed

Huang, Wei Tao; Luo, Hong Qun; Li, Nian Bing

2014-05-06

The most serious, and yet unsolved, problem of constructing molecular computing devices consists in connecting all of these molecular events into a usable device. This report demonstrates the use of Boolean logic tree for analyzing the chemical event network based on graphene, organic dye, thrombin aptamer, and Fenton reaction, organizing and connecting these basic chemical events. And this chemical event network can be utilized to implement fluorescent combinatorial logic (including basic logic gates and complex integrated logic circuits) and fuzzy logic computing. On the basis of the Boolean logic tree analysis and logic computing, these basic chemical events can be considered as programmable "words" and chemical interactions as "syntax" logic rules to construct molecular search engine for performing intelligent molecular search query. Our approach is helpful in developing the advanced logic program based on molecules for application in biosensing, nanotechnology, and drug delivery.

The Optimization of In-Memory Space Partitioning Trees for Cache Utilization

NASA Astrophysics Data System (ADS)

Yeo, Myung Ho; Min, Young Soo; Bok, Kyoung Soo; Yoo, Jae Soo

In this paper, a novel cache conscious indexing technique based on space partitioning trees is proposed. Many researchers investigated efficient cache conscious indexing techniques which improve retrieval performance of in-memory database management system recently. However, most studies considered data partitioning and targeted fast information retrieval. Existing data partitioning-based index structures significantly degrade performance due to the redundant accesses of overlapped spaces. Specially, R-tree-based index structures suffer from the propagation of MBR (Minimum Bounding Rectangle) information by updating data frequently. In this paper, we propose an in-memory space partitioning index structure for optimal cache utilization. The proposed index structure is compared with the existing index structures in terms of update performance, insertion performance and cache-utilization rate in a variety of environments. The results demonstrate that the proposed index structure offers better performance than existing index structures.

Development of a distributed air pollutant dry deposition modeling framework.

PubMed

Hirabayashi, Satoshi; Kroll, Charles N; Nowak, David J

2012-12-01

A distributed air pollutant dry deposition modeling system was developed with a geographic information system (GIS) to enhance the functionality of i-Tree Eco (i-Tree, 2011). With the developed system, temperature, leaf area index (LAI) and air pollutant concentration in a spatially distributed form can be estimated, and based on these and other input variables, dry deposition of carbon monoxide (CO), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), and particulate matter less than 10 microns (PM10) to trees can be spatially quantified. Employing nationally available road network, traffic volume, air pollutant emission/measurement and meteorological data, the developed system provides a framework for the U.S. city managers to identify spatial patterns of urban forest and locate potential areas for future urban forest planting and protection to improve air quality. To exhibit the usability of the framework, a case study was performed for July and August of 2005 in Baltimore, MD. Copyright © 2012 Elsevier Ltd. All rights reserved.

Integrated Approach To Design And Analysis Of Systems

NASA Technical Reports Server (NTRS)

Patterson-Hine, F. A.; Iverson, David L.

1993-01-01

Object-oriented fault-tree representation unifies evaluation of reliability and diagnosis of faults. Programming/fault tree described more fully in "Object-Oriented Algorithm For Evaluation Of Fault Trees" (ARC-12731). Augmented fault tree object contains more information than fault tree object used in quantitative analysis of reliability. Additional information needed to diagnose faults in system represented by fault tree.

Representations of the language recognition problem for a theorem prover

NASA Technical Reports Server (NTRS)

Minker, J.; Vanderbrug, G. J.

1972-01-01

Two representations of the language recognition problem for a theorem prover in first order logic are presented and contrasted. One of the representations is based on the familiar method of generating sentential forms of the language, and the other is based on the Cocke parsing algorithm. An augmented theorem prover is described which permits recognition of recursive languages. The state-transformation method developed by Cordell Green to construct problem solutions in resolution-based systems can be used to obtain the parse tree. In particular, the end-order traversal of the parse tree is derived in one of the representations. An inference system, termed the cycle inference system, is defined which makes it possible for the theorem prover to model the method on which the representation is based. The general applicability of the cycle inference system to state space problems is discussed. Given an unsatisfiable set S, where each clause has at most one positive literal, it is shown that there exists an input proof. The clauses for the two representations satisfy these conditions, as do many state space problems.

A hydraulic-photosynthetic model based on extended HLH and its application to Coast redwood (Sequoia sempervirens).

PubMed

Du, Ning; Fan, Jintu; Chen, Shuo; Liu, Yang

2008-07-21

Although recent investigations [Ryan, M.G., Yoder, B.J., 1997. Hydraulic limits to tree height and tree growth. Bioscience 47, 235-242; Koch, G.W., Sillett, S.C.,Jennings, G.M.,Davis, S.D., 2004. The limits to tree height. Nature 428, 851-854; Niklas, K.J., Spatz, H., 2004. Growth and hydraulic (not mechanical) constraints govern the scaling of tree height and mass. Proc. Natl Acad. Sci. 101, 15661-15663; Ryan, M.G., Phillips, N., Bond, B.J., 2006. Hydraulic limitation hypothesis revisited. Plant Cell Environ. 29, 367-381; Niklas, K.J., 2007. Maximum plant height and the biophysical factors that limit it. Tree Physiol. 27, 433-440; Burgess, S.S.O., Dawson, T.E., 2007. Predicting the limits to tree height using statistical regressions of leaf traits. New Phytol. 174, 626-636] suggested that the hydraulic limitation hypothesis (HLH) is the most plausible theory to explain the biophysical limits to maximum tree height and the decline in tree growth rate with age, the analysis is largely qualitative or based on statistical regression. Here we present an integrated biophysical model based on the principle that trees develop physiological compensations (e.g. the declined leaf water potential and the tapering of conduits with heights [West, G.B., Brown, J.H., Enquist, B.J., 1999. A general model for the structure and allometry of plant vascular systems. Nature 400, 664-667]) to resist the increasing water stress with height, the classical HLH and the biochemical limitations on photosynthesis [von Caemmerer, S., 2000. Biochemical Models of Leaf Photosynthesis. CSIRO Publishing, Australia]. The model has been applied to the tallest trees in the world (viz. Coast redwood (Sequoia sempervirens)). Xylem water potential, leaf carbon isotope composition, leaf mass to area ratio at different heights derived from the model show good agreements with the experimental measurements of Koch et al. [2004. The limits to tree height. Nature 428, 851-854]. The model also well explains the universal trend of declining growth rate with age.

Tree physiology research in a changing world.

PubMed

Kaufmann, Merrill R.; Linder, Sune

1996-01-01

Changes in issues and advances in methodology have contributed to substantial progress in tree physiology research during the last several decades. Current research focuses on process interactions in complex systems and the integration of processes across multiple spatial and temporal scales. An increasingly important challenge for future research is assuring sustainability of production systems and forested ecosystems in the face of increased demands for natural resources and human disturbance of forests. Meeting this challenge requires significant shifts in research approach, including the study of limitations of productivity that may accompany achievement of system sustainability, and a focus on the biological capabilities of complex land bases altered by human activity.

A robotic vision system to measure tree traits

USDA-ARS?s Scientific Manuscript database

The autonomous measurement of tree traits, such as branching structure, branch diameters, branch lengths, and branch angles, is required for tasks such as robotic pruning of trees as well as structural phenotyping. We propose a robotic vision system called the Robotic System for Tree Shape Estimati...

Dynamic and Contextual Information in HMM Modeling for Handwritten Word Recognition.

PubMed

Bianne-Bernard, Anne-Laure; Menasri, Farès; Al-Hajj Mohamad, Rami; Mokbel, Chafic; Kermorvant, Christopher; Likforman-Sulem, Laurence

2011-10-01

This study aims at building an efficient word recognition system resulting from the combination of three handwriting recognizers. The main component of this combined system is an HMM-based recognizer which considers dynamic and contextual information for a better modeling of writing units. For modeling the contextual units, a state-tying process based on decision tree clustering is introduced. Decision trees are built according to a set of expert-based questions on how characters are written. Questions are divided into global questions, yielding larger clusters, and precise questions, yielding smaller ones. Such clustering enables us to reduce the total number of models and Gaussians densities by 10. We then apply this modeling to the recognition of handwritten words. Experiments are conducted on three publicly available databases based on Latin or Arabic languages: Rimes, IAM, and OpenHart. The results obtained show that contextual information embedded with dynamic modeling significantly improves recognition.

On the Suitability of Suffix Arrays for Lempel-Ziv Data Compression

NASA Astrophysics Data System (ADS)

Ferreira, Artur J.; Oliveira, Arlindo L.; Figueiredo, Mário A. T.

Lossless compression algorithms of the Lempel-Ziv (LZ) family are widely used nowadays. Regarding time and memory requirements, LZ encoding is much more demanding than decoding. In order to speed up the encoding process, efficient data structures, like suffix trees, have been used. In this paper, we explore the use of suffix arrays to hold the dictionary of the LZ encoder, and propose an algorithm to search over it. We show that the resulting encoder attains roughly the same compression ratios as those based on suffix trees. However, the amount of memory required by the suffix array is fixed, and much lower than the variable amount of memory used by encoders based on suffix trees (which depends on the text to encode). We conclude that suffix arrays, when compared to suffix trees in terms of the trade-off among time, memory, and compression ratio, may be preferable in scenarios (e.g., embedded systems) where memory is at a premium and high speed is not critical.

Foraging Behaviour in Magellanic Woodpeckers Is Consistent with a Multi-Scale Assessment of Tree Quality

PubMed Central

Vergara, Pablo M.; Soto, Gerardo E.; Rodewald, Amanda D.; Meneses, Luis O.; Pérez-Hernández, Christian G.

2016-01-01

Theoretical models predict that animals should make foraging decisions after assessing the quality of available habitat, but most models fail to consider the spatio-temporal scales at which animals perceive habitat availability. We tested three foraging strategies that explain how Magellanic woodpeckers (Campephilus magellanicus) assess the relative quality of trees: 1) Woodpeckers with local knowledge select trees based on the available trees in the immediate vicinity. 2) Woodpeckers lacking local knowledge select trees based on their availability at previously visited locations. 3) Woodpeckers using information from long-term memory select trees based on knowledge about trees available within the entire landscape. We observed foraging woodpeckers and used a Brownian Bridge Movement Model to identify trees available to woodpeckers along foraging routes. Woodpeckers selected trees with a later decay stage than available trees. Selection models indicated that preferences of Magellanic woodpeckers were based on clusters of trees near the most recently visited trees, thus suggesting that woodpeckers use visual cues from neighboring trees. In a second analysis, Cox’s proportional hazards models showed that woodpeckers used information consolidated across broader spatial scales to adjust tree residence times. Specifically, woodpeckers spent more time at trees with larger diameters and in a more advanced stage of decay than trees available along their routes. These results suggest that Magellanic woodpeckers make foraging decisions based on the relative quality of trees that they perceive and memorize information at different spatio-temporal scales. PMID:27416115

Foraging Behaviour in Magellanic Woodpeckers Is Consistent with a Multi-Scale Assessment of Tree Quality.

PubMed

Vergara, Pablo M; Soto, Gerardo E; Moreira-Arce, Darío; Rodewald, Amanda D; Meneses, Luis O; Pérez-Hernández, Christian G

2016-01-01

Theoretical models predict that animals should make foraging decisions after assessing the quality of available habitat, but most models fail to consider the spatio-temporal scales at which animals perceive habitat availability. We tested three foraging strategies that explain how Magellanic woodpeckers (Campephilus magellanicus) assess the relative quality of trees: 1) Woodpeckers with local knowledge select trees based on the available trees in the immediate vicinity. 2) Woodpeckers lacking local knowledge select trees based on their availability at previously visited locations. 3) Woodpeckers using information from long-term memory select trees based on knowledge about trees available within the entire landscape. We observed foraging woodpeckers and used a Brownian Bridge Movement Model to identify trees available to woodpeckers along foraging routes. Woodpeckers selected trees with a later decay stage than available trees. Selection models indicated that preferences of Magellanic woodpeckers were based on clusters of trees near the most recently visited trees, thus suggesting that woodpeckers use visual cues from neighboring trees. In a second analysis, Cox's proportional hazards models showed that woodpeckers used information consolidated across broader spatial scales to adjust tree residence times. Specifically, woodpeckers spent more time at trees with larger diameters and in a more advanced stage of decay than trees available along their routes. These results suggest that Magellanic woodpeckers make foraging decisions based on the relative quality of trees that they perceive and memorize information at different spatio-temporal scales.

PVEX: An expert system for producibility/value engineering

NASA Technical Reports Server (NTRS)

Lam, Chun S.; Moseley, Warren

1991-01-01

PVEX is described as an expert system that solves the problem of selection of the material and process in missile manufacturing. The producibility and the value problem has been deeply studied in the past years, and was written in dBase III and PROLOG before. A new approach is presented in that the solution is achieved by introducing hypothetical reasoning, heuristic criteria integrated with a simple hypertext system and shell programming. PVEX combines KMS with Unix scripts which graphically depicts decision trees. The decision trees convey high level qualitative problem solving knowledge to users, and a stand-alone help facility and technical documentation is available through KMS. The system developed is considerably less development costly than any other comparable expert system.

Developing silvicultural systems based on partial cutting in western hemlock–Sitka spruce stands of southeast Alaska.

Treesearch

Robert L. Deal; J.C. Tappeiner; Paul E. Hennon

2002-01-01

The effects of partial cutting on species composition, stand structure and growth, tree size distribution, and tree disease and mortality were evaluated on 73 plots in 18 stands that were harvested 12–96 years ago in southeast Alaska. Partially-cut stands had diverse and highly complex stand structures similar to uncut stands. Sitka spruce was maintained in mixed...

A multistage decision support framework to guide tree species management under climate change via habitat suitability and colonization models, and a knowledge-based scoring system

Treesearch

Anantha M. Prasad; Louis R. Iverson; Stephen N. Matthews; Matthew P. Peters

2016-01-01

Context. No single model can capture the complex species range dynamics under changing climates--hence the need for a combination approach that addresses management concerns. Objective. A multistage approach is illustrated to manage forested landscapes under climate change. We combine a tree species habitat model--DISTRIB II, a species colonization model--SHIFT, and...

Transport of root-respired CO₂ via the transpiration stream affects aboveground carbon assimilation and CO₂ efflux in trees.

PubMed

Bloemen, Jasper; McGuire, Mary Anne; Aubrey, Doug P; Teskey, Robert O; Steppe, Kathy

2013-01-01

Upward transport of CO₂ via the transpiration stream from belowground to aboveground tissues occurs in tree stems. Despite potentially important implications for our understanding of plant physiology, the fate of internally transported CO₂ derived from autotrophic respiratory processes remains unclear. We infused a ¹³CO₂-labeled aqueous solution into the base of 7-yr-old field-grown eastern cottonwood (Populus deltoides) trees to investigate the effect of xylem-transported CO₂ derived from the root system on aboveground carbon assimilation and CO₂ efflux. The ¹³C label was transported internally and detected throughout the tree. Up to 17% of the infused label was assimilated, while the remainder diffused to the atmosphere via stem and branch efflux. The largest amount of assimilated ¹³C was found in branch woody tissues, while only a small quantity was assimilated in the foliage. Petioles were more highly enriched in ¹³C than other leaf tissues. Our results confirm a recycling pathway for respired CO₂ and indicate that internal transport of CO₂ from the root system may confound the interpretation of efflux-based estimates of woody tissue respiration and patterns of carbohydrate allocation. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

Towards organ printing: engineering an intra-organ branched vascular tree

PubMed Central

Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

2013-01-01

Importance of the field Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. Areas covered in this review We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. What the reader will gain The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. Take home message It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a ‘built in’ intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a ‘built in’ intra-organ branched vascular tree. PMID:20132061

Tree species effects on topsoil properties in an old tropical plantation

NASA Astrophysics Data System (ADS)

Bauters, Marijn; Boeckx, Pascal; Ampoorter, Evy; Verbeeck, Hans; Döetterl, Sebastian; Baert, Geert; Verheyen, Kris

2016-04-01

Forest biogeochemistry is strongly linked to the functional strategies of the tree community and the topsoil. Research has long documented that tree species affect soil properties in forests. Our current understanding on this interaction is mainly based on common garden experiments in temperate forest and needs to be extended to other ecosystems if we want to understand this interaction in natural forests worldwide. Using a 77-year-old tropical experimental plantation from central Africa, we examined the relationship between canopy and litter chemical traits and topsoil properties. By the current diversity in this site, the unique setup allowed us to extend the current knowledge from temperate and simplified systems to near-natural tropical forests, and thus bridge the gap between planted monocultures in common gardens, and correlative studies in natural systems. We linked the species-specific leaf and litter chemical traits to the topsoil cation composition, acidity, pH and soil organic matter. We found that average canopy trait values were a better predictor for the topsoil than the litter chemistry. Canopy base cation content positively affected topsoil pH and negatively affected acidity. These, in turn strongly determined the soil organic carbon contents of the topsoil, which ranged a tree-fold in the experiment.

Peak tree: a new tool for multiscale hierarchical representation and peak detection of mass spectrometry data.

PubMed

Zhang, Peng; Li, Houqiang; Wang, Honghui; Wong, Stephen T C; Zhou, Xiaobo

2011-01-01

Peak detection is one of the most important steps in mass spectrometry (MS) analysis. However, the detection result is greatly affected by severe spectrum variations. Unfortunately, most current peak detection methods are neither flexible enough to revise false detection results nor robust enough to resist spectrum variations. To improve flexibility, we introduce peak tree to represent the peak information in MS spectra. Each tree node is a peak judgment on a range of scales, and each tree decomposition, as a set of nodes, is a candidate peak detection result. To improve robustness, we combine peak detection and common peak alignment into a closed-loop framework, which finds the optimal decomposition via both peak intensity and common peak information. The common peak information is derived and loopily refined from the density clustering of the latest peak detection result. Finally, we present an improved ant colony optimization biomarker selection method to build a whole MS analysis system. Experiment shows that our peak detection method can better resist spectrum variations and provide higher sensitivity and lower false detection rates than conventional methods. The benefits from our peak-tree-based system for MS disease analysis are also proved on real SELDI data.

Enabling the use of hereditary information from pedigree tools in medical knowledge-based systems.

PubMed

Gay, Pablo; López, Beatriz; Plà, Albert; Saperas, Jordi; Pous, Carles

2013-08-01

The use of family information is a key issue to deal with inheritance illnesses. This kind of information use to come in the form of pedigree files, which contain structured information as tree or graphs, which explains the family relationships. Knowledge-based systems should incorporate the information gathered by pedigree tools to assess medical decision making. In this paper, we propose a method to achieve such a goal, which consists on the definition of new indicators, and methods and rules to compute them from family trees. The method is illustrated with several case studies. We provide information about its implementation and integration on a case-based reasoning tool. The method has been experimentally tested with breast cancer diagnosis data. The results show the feasibility of our methodology. Copyright © 2013 Elsevier Inc. All rights reserved.

Policy tree optimization for adaptive management of water resources systems

NASA Astrophysics Data System (ADS)

Herman, Jonathan; Giuliani, Matteo

2017-04-01

Water resources systems must cope with irreducible uncertainty in supply and demand, requiring policy alternatives capable of adapting to a range of possible future scenarios. Recent studies have developed adaptive policies based on "signposts" or "tipping points" that suggest the need of updating the policy. However, there remains a need for a general method to optimize the choice of the signposts to be used and their threshold values. This work contributes a general framework and computational algorithm to design adaptive policies as a tree structure (i.e., a hierarchical set of logical rules) using a simulation-optimization approach based on genetic programming. Given a set of feature variables (e.g., reservoir level, inflow observations, inflow forecasts), the resulting policy defines both the optimal reservoir operations and the conditions under which such operations should be triggered. We demonstrate the approach using Folsom Reservoir (California) as a case study, in which operating policies must balance the risk of both floods and droughts. Numerical results show that the tree-based policies outperform the ones designed via Dynamic Programming. In addition, they display good adaptive capacity to the changing climate, successfully adapting the reservoir operations across a large set of uncertain climate scenarios.

Tree water storage and its diurnal dynamics related to sap flow and changes in stem volume in old-growth Douglas-fir trees.

PubMed

Cermák, Jan; Kucera, Jiri; Bauerle, William L; Phillips, Nathan; Hinckley, Thomas M

2007-02-01

Diurnal and seasonal tree water storage was studied in three large Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) trees at the Wind River Canopy Crane Research site. Changes in water storage were based on measurements of sap flow and changes in stem volume and tissue water content at different heights in the stem and branches. We measured sap flow by two variants of the heat balance method (with internal heating in stems and external heating in branches), stem volume with electronic dendrometers, and tissue water content gravimetrically. Water storage was calculated from the differences in diurnal courses of sap flow at different heights and their integration. Old-growth Douglas-fir trees contained large amounts of free water: stem sapwood was the most important storage site, followed by stem phloem, branch sapwood, branch phloem and needles. There were significant time shifts (minutes to hours) between sap flow measured at different positions within the transport system (i.e., stem base to shoot tip), suggesting a highly elastic transport system. On selected fine days between late July and early October, when daily transpiration ranged from 150 to 300 liters, the quantity of stored water used daily ranged from 25 to 55 liters, i.e., about 20% of daily total sap flow. The greatest amount of this stored water came from the lower stem; however, proportionally more water was removed from the upper parts of the tree relative to their water storage capacity. In addition to lags in sap flow from one point in the hydrolic pathway to another, the withdrawal and replacement of stored water was reflected in changes in stem volume. When point-to-point lags in sap flow (minutes to hours near the top and stem base, respectively) were considered, there was a strong linear relationship between stem volume changes and transpiration. Volume changes of the whole tree were small (equivalent to 14% of the total daily use of stored water) indicating that most stored water came from the stem and from its inelastic (sapwood) tissues. Whole tree transpiration can be maintained with stored water for about a week, but it can be maintained with stored water from the upper crown alone for no more than a few hours.

Managing for Multifunctionality in Perennial Grain Crops

PubMed Central

Ryan, Matthew R; Crews, Timothy E; Culman, Steven W; DeHaan, Lee R; Hayes, Richard C; Jungers, Jacob M; Bakker, Matthew G

2018-01-01

Abstract Plant breeders are increasing yields and improving agronomic traits in several perennial grain crops, the first of which is now being incorporated into commercial food products. Integration strategies and management guidelines are needed to optimize production of these new crops, which differ substantially from both annual grain crops and perennial forages. To offset relatively low grain yields, perennial grain cropping systems should be multifunctional. Growing perennial grains for several years to regenerate soil health before rotating to annual crops and growing perennial grains on sloped land and ecologically sensitive areas to reduce soil erosion and nutrient losses are two strategies that can provide ecosystem services and support multifunctionality. Several perennial cereals can be used to produce both grain and forage, and these dual-purpose crops can be intercropped with legumes for additional benefits. Highly diverse perennial grain polycultures can further enhance ecosystem services, but increased management complexity might limit their adoption. PMID:29662249

ETE: a python Environment for Tree Exploration.

PubMed

Huerta-Cepas, Jaime; Dopazo, Joaquín; Gabaldón, Toni

2010-01-13

Many bioinformatics analyses, ranging from gene clustering to phylogenetics, produce hierarchical trees as their main result. These are used to represent the relationships among different biological entities, thus facilitating their analysis and interpretation. A number of standalone programs are available that focus on tree visualization or that perform specific analyses on them. However, such applications are rarely suitable for large-scale surveys, in which a higher level of automation is required. Currently, many genome-wide analyses rely on tree-like data representation and hence there is a growing need for scalable tools to handle tree structures at large scale. Here we present the Environment for Tree Exploration (ETE), a python programming toolkit that assists in the automated manipulation, analysis and visualization of hierarchical trees. ETE libraries provide a broad set of tree handling options as well as specific methods to analyze phylogenetic and clustering trees. Among other features, ETE allows for the independent analysis of tree partitions, has support for the extended newick format, provides an integrated node annotation system and permits to link trees to external data such as multiple sequence alignments or numerical arrays. In addition, ETE implements a number of built-in analytical tools, including phylogeny-based orthology prediction and cluster validation techniques. Finally, ETE's programmable tree drawing engine can be used to automate the graphical rendering of trees with customized node-specific visualizations. ETE provides a complete set of methods to manipulate tree data structures that extends current functionality in other bioinformatic toolkits of a more general purpose. ETE is free software and can be downloaded from http://ete.cgenomics.org.

ETE: a python Environment for Tree Exploration

PubMed Central

2010-01-01

Background Many bioinformatics analyses, ranging from gene clustering to phylogenetics, produce hierarchical trees as their main result. These are used to represent the relationships among different biological entities, thus facilitating their analysis and interpretation. A number of standalone programs are available that focus on tree visualization or that perform specific analyses on them. However, such applications are rarely suitable for large-scale surveys, in which a higher level of automation is required. Currently, many genome-wide analyses rely on tree-like data representation and hence there is a growing need for scalable tools to handle tree structures at large scale. Results Here we present the Environment for Tree Exploration (ETE), a python programming toolkit that assists in the automated manipulation, analysis and visualization of hierarchical trees. ETE libraries provide a broad set of tree handling options as well as specific methods to analyze phylogenetic and clustering trees. Among other features, ETE allows for the independent analysis of tree partitions, has support for the extended newick format, provides an integrated node annotation system and permits to link trees to external data such as multiple sequence alignments or numerical arrays. In addition, ETE implements a number of built-in analytical tools, including phylogeny-based orthology prediction and cluster validation techniques. Finally, ETE's programmable tree drawing engine can be used to automate the graphical rendering of trees with customized node-specific visualizations. Conclusions ETE provides a complete set of methods to manipulate tree data structures that extends current functionality in other bioinformatic toolkits of a more general purpose. ETE is free software and can be downloaded from http://ete.cgenomics.org. PMID:20070885

Responses of Tree Growths to Tree Size, Competition, and Topographic Conditions in Sierra Nevada Forests Using Bi-temporal Airborne LiDAR Data

NASA Astrophysics Data System (ADS)

Ma, Q.; Su, Y.; Tao, S.; Guo, Q.

2016-12-01

Trees in the Sierra Nevada (SN) forests are experiencing rapid changes due to human disturbances and climatic changes. An improved monitoring of tree growth and understanding of how tree growth responses to different impact factors, such as tree competition, forest density, topographic and hydrologic conditions, are urgently needed in tree growth modeling. Traditional tree growth modeling mainly relied on field survey, which was highly time-consuming and labor-intensive. Airborne Light detection and ranging System (ALS) is increasingly used in forest survey, due to its high efficiency and accuracy in three-dimensional tree structure delineation and terrain characterization. This study successfully detected individual tree growth in height (ΔH), crown area (ΔA), and crown volume (ΔV) over a five-year period (2007-2012) using bi-temporal ALS data in two conifer forest areas in SN. We further analyzed their responses to original tree size, competition indices, forest structure indices, and topographic environmental parameters at individual tree and forest stand scales. Our results indicated ΔH was strongly sensitive to topographic wetness index; whereas ΔA and ΔV were highly responsive to forest density and original tree sizes. These ALS based findings in ΔH were consistent with field measurements. Our study demonstrated the promising potential of using bi-temporal ALS data in forest growth measurements and analysis. A more comprehensive study over a longer temporal period and a wider range of forest stands would give better insights into tree growth in the SN, and provide useful guides for forest growth monitoring, modeling, and management.

A tree-like Bayesian structure learning algorithm for small-sample datasets from complex biological model systems.

PubMed

Yin, Weiwei; Garimalla, Swetha; Moreno, Alberto; Galinski, Mary R; Styczynski, Mark P

2015-08-28

There are increasing efforts to bring high-throughput systems biology techniques to bear on complex animal model systems, often with a goal of learning about underlying regulatory network structures (e.g., gene regulatory networks). However, complex animal model systems typically have significant limitations on cohort sizes, number of samples, and the ability to perform follow-up and validation experiments. These constraints are particularly problematic for many current network learning approaches, which require large numbers of samples and may predict many more regulatory relationships than actually exist. Here, we test the idea that by leveraging the accuracy and efficiency of classifiers, we can construct high-quality networks that capture important interactions between variables in datasets with few samples. We start from a previously-developed tree-like Bayesian classifier and generalize its network learning approach to allow for arbitrary depth and complexity of tree-like networks. Using four diverse sample networks, we demonstrate that this approach performs consistently better at low sample sizes than the Sparse Candidate Algorithm, a representative approach for comparison because it is known to generate Bayesian networks with high positive predictive value. We develop and demonstrate a resampling-based approach to enable the identification of a viable root for the learned tree-like network, important for cases where the root of a network is not known a priori. We also develop and demonstrate an integrated resampling-based approach to the reduction of variable space for the learning of the network. Finally, we demonstrate the utility of this approach via the analysis of a transcriptional dataset of a malaria challenge in a non-human primate model system, Macaca mulatta, suggesting the potential to capture indicators of the earliest stages of cellular differentiation during leukopoiesis. We demonstrate that by starting from effective and efficient approaches for creating classifiers, we can identify interesting tree-like network structures with significant ability to capture the relationships in the training data. This approach represents a promising strategy for inferring networks with high positive predictive value under the constraint of small numbers of samples, meeting a need that will only continue to grow as more high-throughput studies are applied to complex model systems.

A Wireless Sensor Network for Growth Environment Measurement and Multi-Band Optical Sensing to Diagnose Tree Vigor

PubMed Central

Kameoka, Shinichi; Isoda, Shuhei; Hashimoto, Atsushi; Ito, Ryoei; Miyamoto, Satoru; Wada, Genki; Watanabe, Naoki; Yamakami, Takashi; Suzuki, Ken; Kameoka, Takaharu

2017-01-01

We have tried to develop the guidance system for farmers to cultivate using various phenological indices. As the sensing part of this system, we deployed a new Wireless Sensor Network (WSN). This system uses the 920 MHz radio wave based on the Wireless Smart Utility Network that enables long-range wireless communication. In addition, the data acquired by the WSN were standardized for the advanced web service interoperability. By using these standardized data, we can create a web service that offers various kinds of phenological indices as secondary information to the farmers in the field. We have also established the field management system using thermal image, fluorescent and X-ray fluorescent methods, which enable the nondestructive, chemical-free, simple, and rapid measurement of fruits or trees. We can get the information about the transpiration of plants through a thermal image. The fluorescence sensor gives us information, such as nitrate balance index (NBI), that shows the nitrate balance inside the leaf, chlorophyll content, flavonol content and anthocyanin content. These methods allow one to quickly check the health of trees and find ways to improve the tree vigor of weak ones. Furthermore, the fluorescent x-ray sensor has the possibility to quantify the loss of minerals necessary for fruit growth. PMID:28448452

A Wireless Sensor Network for Growth Environment Measurement and Multi-Band Optical Sensing to Diagnose Tree Vigor.

PubMed

Kameoka, Shinichi; Isoda, Shuhei; Hashimoto, Atsushi; Ito, Ryoei; Miyamoto, Satoru; Wada, Genki; Watanabe, Naoki; Yamakami, Takashi; Suzuki, Ken; Kameoka, Takaharu

2017-04-27

We have tried to develop the guidance system for farmers to cultivate using various phenological indices. As the sensing part of this system, we deployed a new Wireless Sensor Network (WSN). This system uses the 920 MHz radio wave based on the Wireless Smart Utility Network that enables long-range wireless communication. In addition, the data acquired by the WSN were standardized for the advanced web service interoperability. By using these standardized data, we can create a web service that offers various kinds of phenological indices as secondary information to the farmers in the field. We have also established the field management system using thermal image, fluorescent and X-ray fluorescent methods, which enable the nondestructive, chemical-free, simple, and rapid measurement of fruits or trees. We can get the information about the transpiration of plants through a thermal image. The fluorescence sensor gives us information, such as nitrate balance index (NBI), that shows the nitrate balance inside the leaf, chlorophyll content, flavonol content and anthocyanin content. These methods allow one to quickly check the health of trees and find ways to improve the tree vigor of weak ones. Furthermore, the fluorescent x-ray sensor has the possibility to quantify the loss of minerals necessary for fruit growth.

Classification of Parkinsonian syndromes from FDG-PET brain data using decision trees with SSM/PCA features.

PubMed

Mudali, D; Teune, L K; Renken, R J; Leenders, K L; Roerdink, J B T M

2015-01-01

Medical imaging techniques like fluorodeoxyglucose positron emission tomography (FDG-PET) have been used to aid in the differential diagnosis of neurodegenerative brain diseases. In this study, the objective is to classify FDG-PET brain scans of subjects with Parkinsonian syndromes (Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy) compared to healthy controls. The scaled subprofile model/principal component analysis (SSM/PCA) method was applied to FDG-PET brain image data to obtain covariance patterns and corresponding subject scores. The latter were used as features for supervised classification by the C4.5 decision tree method. Leave-one-out cross validation was applied to determine classifier performance. We carried out a comparison with other types of classifiers. The big advantage of decision tree classification is that the results are easy to understand by humans. A visual representation of decision trees strongly supports the interpretation process, which is very important in the context of medical diagnosis. Further improvements are suggested based on enlarging the number of the training data, enhancing the decision tree method by bagging, and adding additional features based on (f)MRI data.

[Advances in studies on the structure of farmland shelterbelt ecosystem].

PubMed

Li, Chunping; Guan, Wenbin; Fan, Zhiping; Su, Fanxin; Wang, Xilin

2003-11-01

The ecological function of farmland shelterbelt system is determined by its structure. The spatio-temporal structure is a key aspect in related researches, which is very necessary to study the integrity, stability and durability of shelterbelt modules. In this article, the researches on the structure of farmland shelterbelt ecosystem were reviewed from the four scales of tree structure, shelterbelt structure, shelterbelts network and landscape structure. The principles, methods and productions of each scale were summarized, and the prospects were also discussed. Dynamic simulation of tree growth process in shelterbelts could be conducted by the theory of form and quality structure of tree and by fractal graphics, which were helpful to study the mechanism of individual trees and belts based on photosynthetic and transpiration mechanism of individual trees. The mechanism model of shelterbelt porosity should be conducted, so that, the sustainable yield model of shelterbelt management could be established, and the optimized model of shelterbelt networks with multi-special and multi-hierarchical structure could also be formed. Evaluating the reasonability, stability and durability of shelterbelt landscape based on the theories and methods of landscape ecology was an important task in the future studies.

Managing for Climate Change Adaptation in Forests: a Case Study from the U.S. Southwest

NASA Astrophysics Data System (ADS)

Kerhoulas, L. P.; Kolb, T.; Koch, G. W.; Hurteau, M. D.

2016-12-01

Forest mortality related to climate change is an increasingly common global phenomenon. We provide a case study of the U.S. Southwest to investigate the interactions among forest restoration treatments that alter stand density, tree growth, and drought resistance in trees of different size classes. Using cores taken from five positions in large trees (coarse roots, breast height, base of live crown, mid-crown branch, and treetop) and breast height in small trees, we investigated how radial growth response to thinning and precipitation availability varied in 72 ponderosa pines Pinus ponderosa Dougl. in northern Arizona. Ten years after thinning, growth of small trees did not respond significantly to thinning whereas growth of large trees increased following moderate and heaving thinning, and this response was similar across within-tree core sample positions. The intensity of thinning treatment did not significantly affect dry-year growth in small trees. In large trees, dry-year growth after thinning was maintained at pre-thinning levels in moderate and heavy thinning treatments but decreased in the light thinning and control treatments. Our findings indicate that more aggressive thinning treatments used for forest restoration stimulate growth throughout large residual trees from coarse roots to branches and also improve drought resistance, providing a greater resilience to future climate-related stress. These responses to treatment are more pronounced in large trees than small trees. Forest thinning is therefore recommended in systems that are likely to experience increased temperature and decreased precipitation as a result of climate change.

An embedded real-time red peach detection system based on an OV7670 camera, ARM cortex-M4 processor and 3D look-up tables.

PubMed

Teixidó, Mercè; Font, Davinia; Pallejà, Tomàs; Tresanchez, Marcel; Nogués, Miquel; Palacín, Jordi

2012-10-22

This work proposes the development of an embedded real-time fruit detection system for future automatic fruit harvesting. The proposed embedded system is based on an ARM Cortex-M4 (STM32F407VGT6) processor and an Omnivision OV7670 color camera. The future goal of this embedded vision system will be to control a robotized arm to automatically select and pick some fruit directly from the tree. The complete embedded system has been designed to be placed directly in the gripper tool of the future robotized harvesting arm. The embedded system will be able to perform real-time fruit detection and tracking by using a three-dimensional look-up-table (LUT) defined in the RGB color space and optimized for fruit picking. Additionally, two different methodologies for creating optimized 3D LUTs based on existing linear color models and fruit histograms were implemented in this work and compared for the case of red peaches. The resulting system is able to acquire general and zoomed orchard images and to update the relative tracking information of a red peach in the tree ten times per second.

An Embedded Real-Time Red Peach Detection System Based on an OV7670 Camera, ARM Cortex-M4 Processor and 3D Look-Up Tables

PubMed Central

Teixidó, Mercè; Font, Davinia; Pallejà, Tomàs; Tresanchez, Marcel; Nogués, Miquel; Palacín, Jordi

2012-01-01

This work proposes the development of an embedded real-time fruit detection system for future automatic fruit harvesting. The proposed embedded system is based on an ARM Cortex-M4 (STM32F407VGT6) processor and an Omnivision OV7670 color camera. The future goal of this embedded vision system will be to control a robotized arm to automatically select and pick some fruit directly from the tree. The complete embedded system has been designed to be placed directly in the gripper tool of the future robotized harvesting arm. The embedded system will be able to perform real-time fruit detection and tracking by using a three-dimensional look-up-table (LUT) defined in the RGB color space and optimized for fruit picking. Additionally, two different methodologies for creating optimized 3D LUTs based on existing linear color models and fruit histograms were implemented in this work and compared for the case of red peaches. The resulting system is able to acquire general and zoomed orchard images and to update the relative tracking information of a red peach in the tree ten times per second. PMID:23202040

Keeping trees as assets

Treesearch

Kevin T. Smith

2009-01-01

Landscape trees have real value and contribute to making livable communities. Making the most of that value requires providing trees with the proper care and attention. As potentially large and long-lived organisms, trees benefit from commitment to regular care that respects the natural tree system. This system captures, transforms, and uses energy to survive, grow,...

Olive Actual “on Year” Yield Forecast Tool Based on the Tree Canopy Geometry Using UAS Imagery

PubMed Central

Sola-Guirado, Rafael R.; Castillo-Ruiz, Francisco J.; Jiménez-Jiménez, Francisco; Blanco-Roldan, Gregorio L.; Gil-Ribes, Jesus A.

2017-01-01

Olive has a notable importance in countries of Mediterranean basin and its profitability depends on several factors such as actual yield, production cost or product price. Actual “on year” Yield (AY) is production (kg tree−1) in “on years”, and this research attempts to relate it with geometrical parameters of the tree canopy. Regression equation to forecast AY based on manual canopy volume was determined based on data acquired from different orchard categories and cultivars during different harvesting seasons in southern Spain. Orthoimages were acquired with unmanned aerial systems (UAS) imagery calculating individual crown for relating to canopy volume and AY. Yield levels did not vary between orchard categories; however, it did between irrigated orchards (7000–17,000 kg ha−1) and rainfed ones (4000–7000 kg ha−1). After that, manual canopy volume was related with the individual crown area of trees that were calculated by orthoimages acquired with UAS imagery. Finally, AY was forecasted using both manual canopy volume and individual tree crown area as main factors for olive productivity. AY forecast only by using individual crown area made it possible to get a simple and cheap forecast tool for a wide range of olive orchards. Finally, the acquired information was introduced in a thematic map describing spatial AY variability obtained from orthoimage analysis that may be a powerful tool for farmers, insurance systems, market forecasts or to detect agronomical problems. PMID:28758945

Geospatial Technologies and i-Tree Echo Inventory for Predicting Climate Change on Urban Environment

NASA Astrophysics Data System (ADS)

Sriharan, S.; Robinson, L.; Ghariban, N.; Comar, M.; Pope, B.; Frey, G.

2015-12-01

Urban forests can be useful both in mitigating climate change and in helping cities adapt to higher temperatures and other impacts of climate change. Understanding and managing the impacts of climate change on the urban forest trees and natural communities will help us maintain their environmental, cultural, and economic benefits. Tree Inventory can provide important information on tree species, height, crown width, overall condition, health and maintenance needs. This presentation will demonstrate that a trees database system is necessary for developing a sustainable urban tree program. Virginia State University (VSU) campus benefits from large number and diversity of trees that are helping us by cleaning the air, retaining water, and providing shade on the buildings to reduce energy cost. The objectives of this study were to develop campus inventory of the trees, identify the tree species, map the locations of the trees with user-friendly tools such as i-Tree Eco and geospatial technologies by assessing the cost/benefit of employing student labor for training and ground validation of the results, and help campus landscape managers implement adaptive responses to climate change impacts. Data was collected on the location, species, and size of trees by using i-Tree urban forestry analysis software. This data was transferred to i-Tree inventory system for demonstrating types of trees, diameter of the trees, height of the trees, and vintage of the trees. The study site was mapped by collecting waypoints with GPS (Global Positioning System) at the trees and uploading these waypoints in ArcMap. The results of this study showed that: (i) students make good field crews, (ii) if more trees were placed in the proper area, the heating and cooling costs will reduce, and (iii) trees database system is necessary for planning, designing, planting, and maintenance, and removal of campus trees Research sponsored by the NIFA Grant, "Urban Forestry Management" (2012-38821-20153).

Modeling tree crown dynamics with 3D partial differential equations.

PubMed

Beyer, Robert; Letort, Véronique; Cournède, Paul-Henry

2014-01-01

We characterize a tree's spatial foliage distribution by the local leaf area density. Considering this spatially continuous variable allows to describe the spatiotemporal evolution of the tree crown by means of 3D partial differential equations. These offer a framework to rigorously take locally and adaptively acting effects into account, notably the growth toward light. Biomass production through photosynthesis and the allocation to foliage and wood are readily included in this model framework. The system of equations stands out due to its inherent dynamic property of self-organization and spontaneous adaptation, generating complex behavior from even only a few parameters. The density-based approach yields spatially structured tree crowns without relying on detailed geometry. We present the methodological fundamentals of such a modeling approach and discuss further prospects and applications.

Accounting carbon storage in decaying root systems of harvested forests.

PubMed

Wang, G Geoff; Van Lear, David H; Hu, Huifeng; Kapeluck, Peter R

2012-05-01

Decaying root systems of harvested trees can be a significant component of belowground carbon storage, especially in intensively managed forests where harvest occurs repeatedly in relatively short rotations. Based on destructive sampling of root systems of harvested loblolly pine trees, we estimated that root systems contained about 32% (17.2 Mg ha(-1)) at the time of harvest, and about 13% (6.1 Mg ha(-1)) of the soil organic carbon 10 years later. Based on the published roundwood output data, we estimated belowground biomass at the time of harvest for loblolly-shortleaf pine forests harvested between 1995 and 2005 in South Carolina. We then calculated C that remained in the decomposing root systems in 2005 using the decay function developed for loblolly pine. Our calculations indicate that the amount of C stored in decaying roots of loblolly-shortleaf pine forests harvested between 1995 and 2005 in South Carolina was 7.1 Tg. Using a simple extrapolation method, we estimated 331.8 Tg C stored in the decomposing roots due to timber harvest from 1995 to 2005 in the conterminous USA. To fully account for the C stored in the decomposing roots of the US forests, future studies need (1) to quantify decay rates of coarse roots for major tree species in different regions, and (2) to develop a methodology that can determine C stock in decomposing roots resulting from natural mortality.

Creating animal models, why not use the Chinese tree shrew (Tupaia belangeri chinensis)?

PubMed

Yao, Yong-Gang

2017-05-18

The Chinese tree shrew ( Tupaia belangeri chinensis ), a squirrel-like and rat-sized mammal, has a wide distribution in Southeast Asia, South and Southwest China and has many unique characteristics that make it suitable for use as an experimental animal. There have been many studies using the tree shrew ( Tupaia belangeri ) aimed at increasing our understanding of fundamental biological mechanisms and for the modeling of human diseases and therapeutic responses. The recent release of a publicly available annotated genome sequence of the Chinese tree shrew and its genome database (www.treeshrewdb.org) has offered a solid base from which it is possible to elucidate the basic biological properties and create animal models using this species. The extensive characterization of key factors and signaling pathways in the immune and nervous systems has shown that tree shrews possess both conserved and unique features relative to primates. Hitherto, the tree shrew has been successfully used to create animal models for myopia, depression, breast cancer, alcohol-induced or non-alcoholic fatty liver diseases, herpes simplex virus type 1 (HSV-1) and hepatitis C virus (HCV) infections, to name a few. The recent successful genetic manipulation of the tree shrew has opened a new avenue for the wider usage of this animal in biomedical research. In this opinion paper, I attempt to summarize the recent research advances that have used the Chinese tree shrew, with a focus on the new knowledge obtained by using the biological properties identified using the tree shrew genome, a proposal for the genome-based approach for creating animal models, and the genetic manipulation of the tree shrew. With more studies using this species and the application of cutting-edge gene editing techniques, the tree shrew will continue to be under the spot light as a viable animal model for investigating the basis of many different human diseases.

Reliability Analysis of Main-axis Control System of the Equatorial Antarctica Astronomical Telescope Based on Fault Tree

NASA Astrophysics Data System (ADS)

LI, Y.; Yang, S. H.

2017-05-01

The Antarctica astronomical telescopes work chronically on the top of the unattended South Pole, and they have only one chance to maintain every year. Due to the complexity of the optical, mechanical, and electrical systems, the telescopes are hard to be maintained and need multi-tasker expedition teams, which means an excessive awareness is essential for the reliability of the Antarctica telescopes. Based on the fault mechanism and fault mode of the main-axis control system for the equatorial Antarctica astronomical telescope AST3-3 (Antarctic Schmidt Telescopes 3-3), the method of fault tree analysis is introduced in this article, and we obtains the importance degree of the top event from the importance degree of the bottom event structure. From the above results, the hidden problems and weak links can be effectively found out, which will indicate the direction for promoting the stability of the system and optimizing the design of the system.

Regolith properties under trees and the biomechanical effects caused by tree root systems as recognized by electrical resistivity tomography (ERT)

NASA Astrophysics Data System (ADS)

Pawlik, Łukasz; Kasprzak, Marek

2018-01-01

Following previous findings regarding the influence of vascular plants (mainly trees) on weathering, soil production and hillslope stability, in this study, we attempted to test a hypothesis regarding significant impacts of tree root systems on soil and regolith properties. Different types of impacts from tree root system (direct and indirect) are commonly gathered under the key term of "biomechanical effects". To add to the discussion of the biomechanical effects of trees, we used a non-invasive geophysical method, electrical resistivity tomography (ERT), to investigate the profiles of four different configurations at three study sites within the Polish section of the Outer Western Carpathians. At each site, one long profile (up to 189 m) of a large section of a hillslope and three short profiles (up to 19.5 m), that is, microsites occupied by trees or their remnants, were made. Short profiles included the tree root zone of a healthy large tree, the tree stump of a decaying tree and the pit-and-mound topography formed after a tree uprooting. The resistivity of regolith and bedrock presented on the long profiles and in comparison with the short profiles through the microsites it can be seen how tree roots impact soil and regolith properties and add to the complexity of the whole soil/regolith profile. Trees change soil and regolith properties directly through root channels and moisture migration and indirectly through the uprooting of trees and the formation of pit-and-mound topography. Within tree stump microsites, the impact of tree root systems, evaluated by a resistivity model, was smaller compared to microsites with living trees or those with pit-and-mound topography but was still visible even several decades after the trees were windbroken or cut down. The ERT method is highly useful for quick evaluation of the impact of tree root systems on soils and regolith. This method, in contrast to traditional soil analyses, offers a continuous dataset for the entire microsite and at depths not normally reached by standard soil excavations. The non-invasive nature of ERT studies is especially important for protected areas as it was shown in the present study.

Environmental safety to decomposer invertebrates of azadirachtin (neem) as a systemic insecticide in trees to control emerald ash borer.

PubMed

Kreutzweiser, David; Thompson, Dean; Grimalt, Susana; Chartrand, Derek; Good, Kevin; Scarr, Taylor

2011-09-01

The non-target effects of an azadirachtin-based systemic insecticide used for control of wood-boring insect pests in trees were assessed on litter-dwelling earthworms, leaf-shredding aquatic insects, and microbial communities in terrestrial and aquatic microcosms. The insecticide was injected into the trunks of ash trees at a rate of 0.2 gazadirachtin cm(-1) tree diameter in early summer. At the time of senescence, foliar concentrations in most (65%) leaves where at or below detection (<0.01 mg kg(-1) total azadirachtin) and the average concentration among leaves overall at senescence was 0.19 mg kg(-1). Leaves from the azadirachtin-treated trees at senescence were added to microcosms and responses by test organisms were compared to those in microcosms containing leaves from non-treated ash trees (controls). No significant reductions were detected among earthworm survival, leaf consumption rates, growth rates, or cocoon production, aquatic insect survival and leaf consumption rates, and among terrestrial and aquatic microbial decomposition of leaf material in comparison to controls. In a further set of microcosm tests containing leaves from intentional high-dose trees, the only significant, adverse effect detected was a reduction in microbial decomposition of leaf material, and only at the highest test concentration (∼6 mg kg(-1)). Results indicated no significant adverse effects on litter-dwelling earthworms or leaf-shredding aquatic insects at concentrations up to at least 30 × the expected field concentrations at operational rates, and at 6 × expected field concentrations for adverse effects on microbial decomposition. We conclude that when azadirachtin is used as a systemic insecticide in trees for control of insect pests such as the invasive wood-boring beetle, emerald ash borer, resultant foliar concentrations in senescent leaf material are likely to pose little risk of harm to decomposer invertebrates. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

Convergence of Mayer and Virial expansions and the Penrose tree-graph identity

NASA Astrophysics Data System (ADS)

Procacci, Aldo; Yuhjtman, Sergio A.

2017-01-01

We establish new lower bounds for the convergence radius of the Mayer series and the Virial series of a continuous particle system interacting via a stable and tempered pair potential. Our bounds considerably improve those given by Penrose (J Math Phys 4:1312, 1963) and Ruelle (Ann Phys 5:109-120, 1963) for the Mayer series and by Lebowitz and Penrose (J Math Phys 7:841-847, 1964) for the Virial series. To get our results, we exploit the tree-graph identity given by Penrose (Statistical mechanics: foundations and applications. Benjamin, New York, 1967) using a new partition scheme based on minimum spanning trees.

Efficient algorithms for a class of partitioning problems

NASA Technical Reports Server (NTRS)

Iqbal, M. Ashraf; Bokhari, Shahid H.

1990-01-01

The problem of optimally partitioning the modules of chain- or tree-like tasks over chain-structured or host-satellite multiple computer systems is addressed. This important class of problems includes many signal processing and industrial control applications. Prior research has resulted in a succession of faster exact and approximate algorithms for these problems. Polynomial exact and approximate algorithms are described for this class that are better than any of the previously reported algorithms. The approach is based on a preprocessing step that condenses the given chain or tree structured task into a monotonic chain or tree. The partitioning of this monotonic take can then be carried out using fast search techniques.

An Approach for Implementing a Microcomputer Based Report Origination System in the Ada Programming Language

DTIC Science & Technology

1983-03-01

Decision Tree -------------------- 62 4-E. PACKAGE unitrep Action/Area Selection flow Chart 82 4-7. PACKAGE unitrep Control Flow Chart...the originetor wculd manually draft simple, readable, formatted iressages using "-i predef.ined forms and decision logic trees . This alternative was...Study Analysis DATA CCNTENT ERRORS PERCENT OF ERRORS Character Type 2.1 Calcvlations/Associations 14.3 Message Identification 4.? Value Pisiratch 22.E

Phylogenetic Reconstruction and DNA Barcoding for Closely Related Pine Moth Species (Dendrolimus) in China with Multiple Gene Markers

PubMed Central

Dai, Qing-Yan; Gao, Qiang; Wu, Chun-Sheng; Chesters, Douglas; Zhu, Chao-Dong; Zhang, Ai-Bing

2012-01-01

Unlike distinct species, closely related species offer a great challenge for phylogeny reconstruction and species identification with DNA barcoding due to their often overlapping genetic variation. We tested a sibling species group of pine moth pests in China with a standard cytochrome c oxidase subunit I (COI) gene and two alternative internal transcribed spacer (ITS) genes (ITS1 and ITS2). Five different phylogenetic/DNA barcoding analysis methods (Maximum likelihood (ML)/Neighbor-joining (NJ), “best close match” (BCM), Minimum distance (MD), and BP-based method (BP)), representing commonly used methodology (tree-based and non-tree based) in the field, were applied to both single-gene and multiple-gene analyses. Our results demonstrated clear reciprocal species monophyly for three relatively distant related species, Dendrolimus superans, D. houi, D. kikuchii, as recovered by both single and multiple genes while the phylogenetic relationship of three closely related species, D. punctatus, D. tabulaeformis, D. spectabilis, could not be resolved with the traditional tree-building methods. Additionally, we find the standard COI barcode outperforms two nuclear ITS genes, whatever the methods used. On average, the COI barcode achieved a success rate of 94.10–97.40%, while ITS1 and ITS2 obtained a success rate of 64.70–81.60%, indicating ITS genes are less suitable for species identification in this case. We propose the use of an overall success rate of species identification that takes both sequencing success and assignation success into account, since species identification success rates with multiple-gene barcoding system were generally overestimated, especially by tree-based methods, where only successfully sequenced DNA sequences were used to construct a phylogenetic tree. Non-tree based methods, such as MD, BCM, and BP approaches, presented advantages over tree-based methods by reporting the overall success rates with statistical significance. In addition, our results indicate that the most closely related species D. punctatus, D. tabulaeformis, and D. spectabilis, may be still in the process of incomplete lineage sorting, with occasional hybridizations occurring among them. PMID:22509245

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strauss, Steve; Shevchenko, Olga; Ma, Caiping

The overall goal of this project was to develop and validate sterility systems in poplar with the ultimate goal of fulfilling the basic requirements for commercial use. For this, sterility must be complete and stable over multiple growing seasons, cause no detrimental effects on vegetative growth, and successful transformation events must be identifiable via molecular tests when trees are still juvenile. Because of the inherent difficulties in achieving and demonstrating complete sterility in trees, our approach was to study alternate sterility systems in Arabidopsis and/or early-flowering tree systems. The public benefit from this work is the capacity for containment ofmore » genes or exotic forms of trees so they can be of benefit for industry for production of wood, energy, and renewable products, while having minimal impact on wild populations of trees. We tested three methods for engineering sterility: dominant negative mutant (DNM) proteins, floral tissue ablation, and RNA interference (RNAi) to suppress the expression of several floral regulatory genes. The ultimate goal of this work was to produce a number of transgenic poplars that could be outplanted to enable future assessments of the effectiveness of these transgenic sterility methods. Our attempts to produce ablation constructs that did not interfere with tree health were partially successful. Using the poplar LEAFY gene promoter and the barnase/barstar system, we were able to regenerate plants that grew well in the greenhouse, but they showed poor health in the field. Four of seven DNM genes tested were considered promising enough, based on results in Arabidopsis, to produce transgenic poplars. Single, double, and triple RNAi genes were produced and transformed into poplar. Over all, we produced 1,964 PCR-confirmed transgenic events with 19 different kinds of sterility genes and several kinds of control genes. We propagated 5,640, 6,820, and 7,055 trees for each of three test poplar genotypes, and field plantings were begun in Spring of 2003 and will be finished in Spring 2007. Continued field studies and monitoring will be required to establish if any of the approaches we have taken will prove to be safe for tree health, stable, and provide reliable containment.« less

Tree-Level Hydrodynamic Approach for Improved Stomatal Conductance Parameterization

NASA Astrophysics Data System (ADS)

Mirfenderesgi, G.; Bohrer, G.; Matheny, A. M.; Ivanov, V. Y.

2014-12-01

The land-surface models do not mechanistically resolve hydrodynamic processes within the tree. The Finite-Elements Tree-Crown Hydrodynamics model version 2 (FETCH2) is based on the pervious FETCH model approach, but with finite difference numerics, and simplified single-beam conduit system. FETCH2 simulates water flow through the tree as a simplified system of porous media conduits. It explicitly resolves spatiotemporal hydraulic stresses throughout the tree's vertical extent that cannot be easily represented using other stomatal-conductance models. Empirical equations relate water potential at the stem to stomata conductance at leaves connected to the stem (through unresolved branches) at that height. While highly simplified, this approach bring some realism to the simulation of stomata conductance because the stomata can respond to stem water potential, rather than an assumed direct relationship with soil moisture, as is currently the case in almost all models. By enabling mechanistic simulation of hydrological traits, such as xylem conductivity, conductive area per DBH, vertical distribution of leaf area and maximal and minimal water content in the xylem, and their effect of the dynamics of water flow in the tree system, the FETCH2 modeling system enhanced our understanding of the role of hydraulic limitations on an experimental forest plot short-term water stresses that lead to tradeoffs between water and light availability for transpiring leaves in forest ecosystems. FETCH2 is particularly suitable to resolve the effects of structural differences between tree and species and size groups, and the consequences of differences in hydraulic strategies of different species. We leverage on a large dataset of sap flow from 60 trees of 4 species at our experimental plot at the University of Michigan Biological Station. Comparison of the sap flow and transpiration patterns in this site and an undisturbed control site shows significant difference in hydraulic strategies between species which affect their response to the disturbance. We used FETCH2 to conduct a sensitivity analysis of the total stand-level transpiration to the inter-specific differences in hydraulic strategies and used the results to reflect on the future trajectory of the forest, in terms of species composition and transpiration.

Cross-Correlations and Structures of Aero-Engine Gas Path System Based on DCCA Coefficient and Rooted Tree

NASA Astrophysics Data System (ADS)

Dong, Keqiang; Fan, Jie; Gao, You

2015-12-01

Identifying the mutual interaction is a crucial problem that facilitates the understanding of emerging structures in complex system. We here focus on aero-engine dynamic as an example of complex system. By applying the detrended cross-correlation analysis (DCCA) coefficient method to aero-engine gas path system, we find that the low-spool rotor speed (N1) and high-spool rotor speed (N2) fluctuation series exhibit cross-correlation characteristic. Further, we employ detrended cross-correlation coefficient matrix and rooted tree to investigate the mutual interactions of other gas path variables. The results can infer that the exhaust gas temperature (EGT), N1, N2, fuel flow (WF) and engine pressure ratio (EPR) are main gas path parameters.