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Land management impacts on tree hole invertebrate communities in a Neotropical rainforest

Journal Articles & Books
Dezembro, 2015
México

The Los Tuxtlas Biosphere Reserve in Southeastern Veracruz, Mexico represents the northernmost Neotropical lowland rainforest and has lost 84 % of its forests in the last forty years. Rich terrestrial and aquatic species communities are found throughout Neotropical forests, habitats increasingly threatened by land management practices. Plant-held waters, phytotelmata, are ecologically important discrete microhabitats harboring many specialist invertebrates and are abundant in tropical forests.

Linking Phenology and Biomass Productivity in South Dakota Mixed-Grass Prairie

Journal Articles & Books
Dezembro, 2013

Assessing the health of rangeland ecosystems based solely on annual biomass production does not fully describe the condition of the plant community; the phenology of production can provide inferences about species composition, successional stage, and grazing impacts. We evaluated the productivity and phenology of western South Dakota mixed-grass prairie in the period from 2000 to 2008 using the normalized difference vegetation index (NDVI). The NDVI is based on 250-m spatial resolution Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery.

Soil structure and soil hydraulic properties of Haplic Luvisol used as arable land and grassland

Journal Articles & Books
Dezembro, 2011
República Checa

This study is focused on the comparison of soil structure and soil hydraulic properties within soil profiles of a same soil type under different land management. Study was performed on Haplic Luvisol in Hněvčeves (Czech Republic). Two soil profiles, which were in close distance from each other, were chosen: under the conventional tillage, and under the 30 years ago reestablished permanent grass cover. Soil structure was analyzed using the micromorphological method.

Crop yield prediction under soil salinity using satellite derived vegetation indices

Journal Articles & Books
Dezembro, 2016

Monitoring the crop yield is one of the key factors to define agricultural land management strategies. Recent developments in spatial information technologies enabled cost and energy saving in crop yield prediction. The aim of this paper was to predict yield of the three major crops and yield loss under soil salinity effect which is one of the most important limitation in many Mediterranean countries. Crop yields were estimated using vegetation indices and Stepwise Linear Regression (SLR) derived from Landsat (Thematic Mapper and Enhanced Thematic Mapper) TM/ETM satellite images.

Ploughing a poorly drained grassland reduced N₂O emissions compared to chemical fallow

Journal Articles & Books
Dezembro, 2011

Managed grasslands occupy a large portion of the agricultural landbase, are rich in C and N and therefore represent a risk for emissions of N₂O during landuse change. Two adjacent grassland plots, one amended with 100m³ ha⁻¹ of liquid swine manure annually since 1978 and an unamended grassland were either (i) left with vegetation intact (Control) or killed by glyphosate in the autumn. Glyphosate-treated subplots were either (ii) left as an undisturbed chemical fallow, (iii) ploughed by full inversion tillage (FIT) in the autumn, or (iv) in the spring.

AN EMPIRICAL ASSESSMENT OF CONVERGENT VALIDITY OF BENEFIT TRANSFER IN CONTINGENT CHOICE: INTRODUCTORY APPLICATIONS WITH NEW CRITERIA

Conference Papers & Reports
Dezembro, 2004

Benefit transfer has been an important, practical policy tool appealing to government agencies, especially when time or budget is constrained. However, the existing literature fails to support convergent validity of benefit transfer using the stated-preference method. This empirical study examines the convergent validity of benefit transfer using the choice modeling method, a potentially promising technique compatible with the heterogeneity of the transfer contexts.

Interactions between ecological and social drivers in determining and managing biodiversity impacts of deer

Journal Articles & Books
Dezembro, 2013

The management of wildlife and its impacts on biodiversity is likely to be most successful where ecological understanding is integrated with the economic and social drivers for management, and where the attitudes and behaviour of stakeholders are fully understood. Collaboration between stakeholders at the landscape level is suggested as the most efficient ‘model’ for the management of many wildlife species such as deer. However, there has been limited research to evaluate the effectiveness of collaborative management for deer or how it is perceived by individual landowners.

Field Validation of DNDC Model for Methane and Nitrous Oxide Emissions from Rice-based Production Systems of India

Journal Articles & Books
Dezembro, 2006
Índia

The DNDC (DeNitrification and DeComposition) model was tested against experimental data on CH₄ and N₂O emissions from rice fields at different geographical locations in India. There was a good agreement between the simulated and observed values of CH₄ and N₂O emissions. The difference between observed and simulated CH₄ emissions in all sites ranged from −11.6 to 62.5 kg C ha⁻¹ season⁻¹. Most discrepancies between simulated and observed seasonal fluxes were less than 20% of the field estimate of the seasonal flux.

Estimating Fuel Consumption for the Upper Coastal Plain of South Carolina

Journal Articles & Books
Dezembro, 2010

Recent changes in air quality regulations present a potential obstacle to continued use of prescribed fire as a land management tool. Lowering of the acceptable daily concentration of particulate matter from 65 to 35 μg/m3 will bring much closer scrutiny of prescribed burning practices from the air quality community. To work within this narrow window, land managers need simple tools to allow them to estimate their potential emissions and examine trade-offs between continued use of prescribed fire and other means of fuels management.

Long-term functioning of a species-rich mountain meadow under different management regimes

Journal Articles & Books
Dezembro, 2009

The aim of this study is to assess the effect of different management practices on mountain meadow plant biomass, species richness and diversity. The experiment was carried out in the Bohemian Forest Mts. at the altitude of 1150-1170m for 10 years. We applied three treatments (mowing, mulching - i.e., cutting and crushing of the sward into small pieces which are left at the site to decompose, abandonment - fallow) to a mountain meadow with dominant Deschampsia cespitosa, Agrostis capillaris, Festuca rubra and Hypericum maculatum.