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1.
ABSTRACT

The Ohio State University Libraries was one of 19 institutions collaborating in the Ithaka S+R Research Support Services for the Field of Agriculture study. Based on a series of individual, semistructured interviews with faculty researchers affiliated with the agricultural sciences at the Ohio State University, the study gathered information about current research practices. The study highlighted challenges of the agricultural research process and identified opportunities for improving research support services for agricultural scientists.  相似文献   

2.
Wu  Chunfa  Zhang  JinLu  Zhang  Yu  Deng  Shaopo  Wang  Chong  Fu  Zhaocong 《Journal of Soils and Sediments》2022,22(9):2365-2380
Purpose

Phosphorus (P)-containing passivators have a stabilizing effect on cadmium (Cd)-contaminated agricultural soils to be safely used, offering good potential for risk control of Cd-contaminated agricultural soils to be strictly controlled. In this study, an incubation experiment was conducted to evaluate the risk control effects of using hydroxyapatite (HAP) and monocalcium phosphate (MCP) on Cd-contaminated agricultural soils to be strictly controlled.

Materials and methods

Samples of topsoil were collected (0–20 cm) from agricultural land near a lead–zinc mine in Southwestern China containing 32.07 mg kg?1 Cd with a pH of 7.28. The amounts of passivators added were equal to approximately 3% of the soil by weight. The soil Cd content, physicochemical properties, enzyme activity, and microbial community were analyzed.

Results

The results showed that the application of HAP and MCP decreased the activity and mobility of Cd in soils to be strictly controlled. HAP was more effective in decreasing the exchangeable Cd (CdEx) than MCP (rate of decrease was 48.1% for HAP and 24.4% for MCP). According to the results of the geometric mean (GMean) and the integrated total enzyme activity (TEI) index, the total soil enzyme activity of the HAP treatment was higher than that of CK and MCP treatment. HAP and MCP significantly decreased the Chao and Shannon bacterial community indices and the Shannon index of the soil fungal community. HAP increased Actinobacteria abundance, which is beneficial to soil fertility enhancement and plant growth, and MCP increased Rhizobiales abundance, which promotes soil P cycling and plant growth. Primary driving factors for the changes in bacterial and fungal community composition in the stabilized soils were CEC and CdEx for bacteria and Cd bound to carbonates (CdCar) and residual Cd (CdRes) for fungi.

Conclusions

HAP is more suitable for risk control of Cd-contaminated agricultural soils to be strictly controlled than MCP from the perspective of soil Cd activity and mobility, soil enzyme activity, and diversity and composition of the soil microbial community.

  相似文献   

3.
ABSTRACT

The purpose of this study was to develop a core list of journals for the field of agricultural economics. For this study, the holdings of members of the Agricultural Economics Reference Organization who represent agricultural economics libraries in the U.S. and Canada were surveyed. The resulting list of titles is compared to four similar lists, three in agricultural economics and the fourth in economics. Using any one list of journals is inadequate for collection development in agricultural economics. This survey list, along with other similar lists, can be used for decision making in selection and management of journal titles in the field.  相似文献   

4.
Purpose

Roadside ditches line more than 6.3 million km of roadways in the USA, dissecting the natural topography and altering the flow of runoff from the catchments that drain into them. In agricultural regions, more than 30% of a watershed may directly drain into the roadside ditch system. Quantifying soil erosion and sediment export from agricultural watersheds is a crucial component when considering long-term soil sustainability.

Materials and methods

Our study evaluated the relation of catchment soil erosion and ditch sedimentation at six representative roadside ditches in Lime Creek watershed (eastern Iowa) and quantified the effectiveness of possible catchment conservation practices to reduce soil erosion and ditch sedimentation.

Results and discussion

Study results provide clear evidence linking roadside ditches to the agricultural catchments that drain into them. Among the six ditch sites, catchment erosion was found to be inversely related to sediment storage within the ditch due to erosive power of water entering the ditches from their basins. Of four catchment scenarios to reduce soil erosion, no-till with cover and graded terrace did not require land to be taken out of production and provided the most significant reductions in catchment erosion rates.

Conclusions

Results indicated that reducing nutrient and sediment loads to ditches by incorporating in-field conservation practices in ditch catchments may be more economical and environmentally sustainable than current management practices for both farmers and roadway managers because they trap detached soil sediments before they enter the ditch.

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5.
Purpose

Sediment fingerprinting is increasingly being used to improve the understanding of sediment dynamics within the critical zone and provide information that can help guide management decisions at the watershed scale. The objectives of this study were to investigate both the implications of different sediment fingerprinting sampling designs and spatial scales on the characterization of sediment dynamics in a predominantly agricultural watershed in northwestern New Brunswick, Canada.

Materials and methods

Color and radionuclide fingerprints were used to discriminate between three potential sediment sources: agricultural topsoil, agricultural streambanks, and forested areas (topsoil and streambanks). Suspended sediment was collected seasonally, between 2008 and 2014, at five sites with drainage areas ranging from 3.0 to 13.4 km2. Using the same source and sediment data set, multiple-, nested-, and local-location fingerprinting sampling designs were employed to investigate the influence of scale of observation, geomorphic connectivity, land use, and the heterogeneity of source fingerprints on apportionment results.

Results and discussion

Sediment collected in the headwaters was primarily derived from forested areas while the sediment collected at the outlet of the watershed was primarily from agricultural topsoil. When comparing the multiple- and nested-location designs, it was found that accounting for the spatial variability in the fingerprint properties of each source had a small difference in the sediment apportionment results. Furthermore, the local-location design demonstrated that the sediment collected at each location was composed of predominately local sources as opposed to upstream sediment entering the local catchment.

Conclusions

Assessment of the sources of sediment at a range of spatial scales better accounts for both geomorphic connectivity and differences in land use throughout the watershed. Overall, each of the three fingerprinting sampling designs provided different information that can be used to guide soil and water conservation management.

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6.
Introduction

In the preceding paper,1) the author pointed out the necessity of investigating the contaminating radioactive elements in agricultural crops. In this paper. a simple radiochemical treatise on the contaminated plants is discussed.  相似文献   

7.
ABSTRACT

Definitions of sustainable agriculture commonly include twin goals of profitability and environmental soundness. This paper focuses on an examination of the incentive systems moving agricultural producers towards achievement of these goals, and on incentive systems that might increase the efficiency of movements toward agricultural sustainability. The feed-back mechanism of the economic incentive system pushing farmers toward profitability is contrasted with the unclear, and sometimes conflicting, incentives offered farmers wishing to move toward more sustainable production systems.  相似文献   

8.
ABSTRACT

Libraries have often played a major role in preserving our agricultural heritage. Many special libraries have helped to assemble the agricultural literature, much of which is in formats traditionally difficult to collect and maintain, particularly those of agricultural significance. This paper presents a brief overview of the changing nature of agricultural communications and how units within special libraries, such as the University of Illinois at Urbana-Champaign's Agricultural Communications Documentation Center (ACDC), play an important role in the creation, dissemination, and archiving of this vital information. Other specialized collections and services, such as the materials of The National Association of Farm Broadcasters (NAFB) and the Agriculture Network Information Center (AgNIC) will also be discussed.  相似文献   

9.
ABSTRACT

In 2016, the Oklahoma State University (OSU) Library was invited to participate in an Ithaka S+R research project with 19 other academic libraries from institutions with strong agricultural programs. This project documents agriculture research practices and needs and reflects a summary of findings from 10 interviews with OSU faculty researchers. This local report is to inform the Library's support for research of the OSU's agricultural faculty. The report was completed on December 1, 2016.  相似文献   

10.
Purpose

This field study was performed to assess the variation in chemical and agronomic properties and total and extractable concentrations of heavy metals in soils fertilized with regulated doses of urban sewage sludge (USS) for 6 consecutive years in the framework of an agronomic treatment program.

Materials and methods

Chemical and agronomical properties, total contents and extractable concentrations of Cd, Cr, Cu, Hg, Ni, Pb and Zn were determined in agricultural soils treated with USS for 6 consecutive years, agricultural soils cultivated using mineral fertilizers and uncultivated soils representative of the local geochemical background.

Results and discussion

USS application caused a decrease in pH and an increase in extractable concentrations of Cr, Cu, Pb and Zn. No organic carbon, total nitrogen and total phosphorus enrichment trend was observed in the treated soils due to biodegradation of the organic compounds supplied by USS. The decomposition of USS organic matter was presumably the main process responsible for the pH decrease in the USS-fertilized soils. There was no heavy metal accumulation in treated soils, and total heavy metal contents were below the corresponding maximum threshold concentrations set by European and Italian legislation. Increased availability of Cr, Cu, Pb and Zn was found in treated soils due to an increase in their extractable concentrations in the treatment period.

Conclusions

The results of this study suggest that the environmental risks related to the accumulation and availability of heavy metals in agricultural soils fertilized with USS are limited when treatment observes recommended doses in agronomic treatment programs.

  相似文献   

11.
ABSTRACT

This study assessed farmers' utilization of agricultural information on Ere Agbe radio broadcasts in the Oke-Ogun Area of Oyo State. Data were collected on appropriateness, utilization of agricultural information, and constraints to access, from 160 farmer-listeners using an interview schedule. The appropriateness of information was low (51.9%); 47.5% utilized information highly; irregular power supply (M = 1.3125) was the main constraint to information access. The perceived appropriateness (r = .89, p ≤ .05) and constraints faced (r = ?0.29, p ≤ .05) were significantly related to utilization of agricultural information. Broadcasts should address farmers' needs, while cheap, alternative power sources should be explored.  相似文献   

12.
Wang  Xiangxiang  Cui  Yongxing  Wang  Yuhan  Duan  Chengjiao  Niu  Yinan  Sun  Ruxiao  Shen  Yufang  Guo  Xuetao  Fang  Linchuan 《Journal of Soils and Sediments》2022,22(2):536-546
Purpose

Variation in soil microbial metabolism remains highly uncertain in predicting soil carbon (C) sequestration, and is particularly and poorly understood in agroecosystem with high soil phosphorus (P) variability.

Materials and methods

This study quantified metabolic limitation of microbes and their association with carbon use efficiency (CUE) via extracellular enzymatic stoichiometry and biogeochemical equilibrium models in field experiment employing five inorganic P gradients (0, 75, 150, 225, and 300 kg P ha?1) in farmland used to grow peas.

Results and discussion

Results showed P fertilization significantly increased soil Olsen-P and NO3?-N contents, and enzyme activities (β-1,4-glucosidase and β-D-cellobiosidase) were significantly affected by P fertilization. It indicated that P fertilization significantly decreased microbial P limitation due to the increase of soil available P. Interestingly, P application also significantly decreased microbial nitrogen (N) limitation, a phenomenon primarily attributable to increasing NO3?-N content via increasing biological N fixation within the pea field. Furthermore, P fertilization increased microbial CUE because the reduction in microbial N and P limitation leads to higher C allocation to microbial growth. Partial least squares path modeling (PLS-PM) further revealed that the reduction of microbial metabolic limitation is conducive to soil C sequestration.

Conclusions

Our study revealed that P application in agroecosystem can alleviate not only microbial P limitation but also N limitation, which further reduces soil C loss via increasing microbial CUE. This study provides important insight into better understanding the mechanisms whereby fertilization mediates soil C cycling driven by microbial metabolism in agricultural ecosystems.

  相似文献   

13.
Abstract

Seven agricultural soils and eight forest soils from Washington state were tested for mineralizable nitrogen using both anaerobic and aerobic incubation procedures. Each procedure had been used previously to. develop nitrogen indices for agricultural and forested ecosystems. Forest soils mineralized less nitrogen under anaerobic than aerobic conditions, while the opposite was true for agricultural soils. There were statistically significant correlations between the two methods for each of the time periods tested. Experimental variations were consistently lower than previously reported.  相似文献   

14.
ABSTRACT

The USDA Economics and Statistics System, which includes data sets and reports from the USDA's ERS, NASS and WAOB is described. The system provides quick and timely access to agricultural statistics on the Internet Step-by-step instructions in searching the system are illustrated.  相似文献   

15.
ABSTRACT

This article presents the results of one of numerous and coordinated qualitative studies carried out at land-grant universities across the United States, to improve our understanding of agricultural research practices and identify new avenues for library services to meet the changing needs of agricultural faculty and research staff. We interviewed agricultural researchers across several departments at Cornell University about their research practices including research dissemination methods, data sharing, their use of primary and secondary resources, and current challenges in conducting agricultural research. Emerging themes included stakeholder engagement, collaboration and interdisciplinarity, the impact of technology, and research inputs and outputs.  相似文献   

16.
ABSTRACT

This article is a report of the 17 interviews conducted in 2016 at Virginia Tech by the agriculture librarian to examine the current state of research and how information professionals can support agricultural researchers. This is one of the reports connected with the larger Ithaka S+R Agriculture Project.  相似文献   

17.
ABSTRACT

Developing countries, Kenya included, continue to put considerable efforts in the creation of scientific agricultural information through the utilization of scientific human resources and an extensive agricultural research system. Little attention has been paid to the management and dissemination of the information so created, especially within the research system, as contrasted with the fanner level. This paper argues that the management and dissemination of information at the level of the research scientists is crucial to the effectiveness of the entire research system, and concludes that Kenya is deficient in this respect.  相似文献   

18.
ABSTRACT

Information technology is perhaps the most pervasive technology in U.S. agriculture. Despite such pervasiveness, the federal government continues to play a crucial role in providing agricultural market information that may be obtained from several sources, including private vendors. Results from a policy survey suggest that seventy-five percent of farmers want the government to continue to play that role. Further results from a logistic regression examine the determinants of that role by examining the influence of several socio-economic variables such as education, membership in agricultural organizations, land tenure and income.  相似文献   

19.
ABSTRACT

Identifying the best source of information to satisfy the needs of local clientele has always been the challenge facing collection development and instruction librarians. In order to provide users with the best possible access tool and source for comprehensive information, it is important that librarians be aware of the most productive sources of information in a field. This paper identifies where the bulk of agricultural economics research is published and indexed. It also ascertains whether Google Scholar is as productive in covering this information as CAB Abstracts and EconLit. The cited reference counts for the top 50 cited sources in Web of Knowledge and Google Scholar are also compared. The scatter of the journal literature in this field, based on the Library of Congress Subject Headings, is also provided. The study identified a broad range of article scattering in areas where agricultural economics and agribusiness materials are published. On the cited reference count, Google Scholar was as productive as the Web of Knowledge. Google Scholar is a free source of very useful information for cited references and other subject searches in the area of agricultural economics and could be used to complement traditional databases.  相似文献   

20.
ABSTRACT

Michigan State University Extension is launching a portal-based information system to help address information delivery, archiving, and cataloging, in addition to geographic dispersion and time and/or budget constraints. The system, expected for public launch during the first quarter of 2005, is described from the planning stages to current configuration. Library staff are cataloging and loading organizational content and helping to develop global content modules. Portal technology facilitates workgroup collaboration–a major design goal in addition to information management and delivery.  相似文献   

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