510,108 research outputs found
Conflict of Laws in the Uniform Commercial Code
Pulsatilla vernalis is one of several endangered plant species that benefit from wildfires and small scale disturbance events that repel competing vegetation and create open patches in the vegetation cover. Previous studies argue that Pulsatilla vernalis is decreasing in numbers due to vegetation changes associated with the decrease in wildfires, forest grazing and changes in forest management. In this study, 17 populations of P. vernalis were inventoried in order to examine if soil and/or vegetation structures affect the population structure of P. vernalis (i.e. population size, presence of flowering individuals, density of juveniles) and if performed conservation attempts in the populations have been positive for P. vernalis. This was done by counting the number of vegetative, flowering and juvenile individuals and examining soil and vegetation structure in the populations. The population sizes were then compared with estimates of population sizes from earlier inventories of P. vernalis at the same localities. The study also presents specific recommendations for an improved conservation management of P. vernalis. The results of this study show that mechanical conservation management had a positive effect on the population size and that open areas in the vegetation cover provided better conditions for viable populations of P. vernalis. To prevent the trend of decreasing population sizes of P. vernalis, conservation measures must be carried out to repel competing vegetation and to restore or maintain open patches in existing populations
Review of best management practices for aquatic vegetation control in stormwater ponds, wetlands, and lakes
Auckland Council (AC) is responsible for the development and operation of a stormwater network across the region to avert risks to citizens and the environment.
Within this stormwater network, aquatic vegetation (including plants, unicellular and filamentous algae) can have both a positive and negative role in stormwater management and water quality treatment. The situations where management is needed to control aquatic vegetation are not always clear, and an inability to identify effective, feasible and economical control options may constrain management initiatives. AC (Infrastructure and Technical Services, Stormwater) commissioned this technical report to provide information for decision- making on aquatic vegetation management with in stormwater systems that are likely to experience vegetation-related issues.
Information was collated from a comprehensive literature review, augmented by knowledge held by the authors. This review identified a wide range of management practices that could be potentially employed. It also demonstrated complexities and uncertainties relating to these options that makes the identification of a best management practice difficult. Hence, the focus of this report was to enable users to screen for potential options, and use reference material provided on each option to confirm the best practice to employ for each situation.
The report identifies factors to define whether there is an aquatic vegetation problem (Section 3.0), and emphasises the need for agreed management goals for control (e.g. reduction, mitigation, containment, eradication). Resources to screen which management option(s) to employ are provided (Section 4.0), relating to the target aquatic vegetation, likely applicability of options to the system being managed, indicative cost, and ease of implementation. Initial screening allows users to shortlist potential control options for further reference (Section 5.0).
Thirty-five control options are described (Section 5.0) in sufficient detail to consider applicability to individual sites and species. These options are grouped under categories of biological, chemical or physical control. Biological control options involve the use of organisms to predate, infect or control vegetation growth (e.g. classical biological control) or manipulate conditions to control algal growth (e.g. pest fish removal, microbial products). Chemical control options involve the use of pesticides and chemicals (e.g. glyphosate, diquat), or the use of flocculants and nutrient inactivation products that are used to reduce nutrient loading, thereby decreasing algal growth. Physical control options involve removing vegetation or algal biomass (e.g. mechanical or manual harvesting), or setting up barriers to their growth (e.g. shading, bottom lining, sediment capping).
Preventative management options are usually the most cost effective, and these are also briefly described (Section 6.0). For example, the use of hygiene or quarantine protocols can reduce weed introductions or spread. Catchment- based practices to reduce sediment and nutrient sources to stormwater are likely to assist in the avoidance of algal and possibly aquatic plant problems. Nutrient removal may be a co-benefit where harvesting of submerged weed biomass is undertaken in stormwater systems. It should also be considered that removal of substantial amounts of submerged vegetation may result in a sudden and difficult-to-reverse s witch to a turbid, phytoplankton dominated state. Another possible solution is the conversion of systems that experience aquatic vegetation issues, to systems that are less likely to experience issues.
The focus of this report is on systems that receive significant stormwater inputs, i.e. constructed bodies, including ponds, amenity lakes, wetlands, and highly-modified receiving bodies. However, some information will have application to other natural water bodies
Forest vegetation management: France (chap.4)
Current practices and problems of forest vegetation management in France are described in the context of research on alternatives to herbicides.FORET;PEUPLEMENT FORESTIER;VEGETATION;CONCURRENCE VEGETALE;LUTTE;MODE DE TRAITEMENT;LUTTE PHYTOSANITAIRE + MAUVAISE HERBE;CONTROLE DE LA VEGETATION;PESTICIDE;HERBICIDE;LUTTE PHYTOSANITAIRE;IMPACT SUR L'ENVIRONNEMENT;DYNAMIQUE DE VEGETATION;HISTOIRE;GESTION FORESTIERE;ECOSYSTEME;FRANCE;VEGETATION FORESTIERE;GESTION;ALTERNATIVES AUX HERBICIDES;ADVENTICE;SPECIES COMPOSITION
Forest vegetation management in Europe: current practice and future requirements
The book provides a record of the co-operation within Europe in the field of forest vegetation management through the Cost Action E47. The aims are: i)to provide a summary of the current state of the art' as it applies to forest vegetation management in Europe for scientists, practitioners and policymakers, affiliated to state, non-governmental or private commercial organizations; ii)to document existing forest weed control practices across Europe, and hence provide a resource of alternative solutions for individual countries sharing similar conditions and challenges; and iii)to identify common information gaps and future research needs, and hence potential future areas of collaboration for forest vegetation management scientists across Europe, along with barriers that may need to be overcome to achieve that aim.FORET;PEUPLEMENT FORESTIER;VEGETATION;CONCURRENCE VEGETALE;LUTTE;MODE DE TRAITEMENT;COOPERATION INTERNATIONALE;RECHERCHE DEVELOPPEMENT;DEVELOPPEMENT DURABLE;AMENAGEMENT FORESTIER;MAUVAISE HERBE;CONTROLE DE LA VEGETATION;PESTICIDE;LUTTE PHYTOSANITAIRE;IMPACT SUR L'ENVIRONNEMENT;DYNAMIQUE DE VEGETATION;HERBICIDE;BIODIVERSITE;ECOSYSTEME;HISTOIRE;GESTION FORESTIERE;EUROPE;VEGETATION FORESTIERE;ADVENTICE;ALTERNATIVES AUX HERBICIDES;
28 years of vegetation change (1978 – 2006) in a calcareous coastal dune system
Changes in vegetation structure and composition over a 28 year period (1978–2006) following removal of human-induced disturbances, were examined in a calcareous coastal dune system in Point Nepean National Park (380 19’S, 1440 41’E) in south-eastern Victoria, Australia. In the early 1980s human habitation of Point Nepean was abandoned and disturbance regimes such as burning, slashing and land clearing were altered or removed, providing an opportunity to study the recovery of disturbed coastal vegetation. Broad-scale and community-level vegetation changes were assessed by comparing quadrat and GIS mapping data from 1978 with data collected in 2006. Results indicate a change in broad vegetation patterns; shrubland vegetation has replaced hind dune grasslands and disturbed areas and there has been a decrease in exposed coastal areas (such as blowouts, dunes and cliffs), and an increase in woody native species and highly invasive woody weeds. The changes highlight the importance of incorporating vegetation states in planning management actions in dynamic coastal vegetation
Inventory and Characterization of the Riparian Zone of the Current and Jacks Fork Rivers
The ecological, recreational, and economic value of the 134 mile (216 km) riparian corridor within the Ozark National Scenic Riverways (ONSR) is of great interest to land managers and conservationists. Recent interest in applying ecosystem management to forest systems has necessitated a fresh look at the tools and methods in use to assess existing patterns of plant community structure and diversity. The purpose and objective of the study described in this report was to initiate a series of vegetation studies that could be integrated with existing research and management infonnation on the riparian vegetation in the ONSR. Defining the compositional and spatial attributes of the riparian corridor were at the core of our research efforts. We used multivariate analysis and ordination techniques to characterize the composition and distribution of woody and herbaceous vegetation within the ONSR
Foreword
This issue of Cunninghamia contains the first two papers of a project involving the classification and assessment of the native vegetation of New South Wales, Australia (NSWVCA). Besides developing a comprehensive typology of the vegetation, the project aims to assess the protected area and threat status of the State’s vegetation. It collates information on vegetation composition, geographic distribution of plant communities, physiographic features, threats, aspects of condition, planning and management and representation in protected areas into a single database system. A photographic library is also being collated for use with the database and use in publications and education programs
Contributions of natural and human factors to increases in vegetation productivity in China
Increasing trends in vegetation productivity have been identified for the last three decades for many regions in the northern hemisphere including China. Multiple natural and human factors are possibly responsible for the increases in vegetation productivity, while their relative contributions remain unclear. Here we analyzed the long-term trends in vegetation productivity in China using the satellite-derived normalized difference vegetation index (NDVI) and assessed the relationships of NDVI with a suite of natural (air temperature, precipitation, photosynthetically active radiation (PAR), atmospheric carbon dioxide (CO2) concentrations, and nitrogen (N) deposition) and human (afforestation and improved agricultural management practices) factors. Overall, China exhibited an increasing trend in vegetation productivity with an increase of 2.7%. At the provincial scale, eleven provinces exhibited significant increases in vegetation productivity, and the majority of these provinces are located within the northern half of the country. At the national scale, annual air temperature was most closely related to NDVI and explained 36.8% of the variance in NDVI, followed by afforestation (25.5%) and crop yield (15.8%). Altogether, temperature, total forest plantation area, and crop yield explained 78.1% of the variance in vegetation productivity at the national scale, while precipitation, PAR, atmospheric CO2 concentrations, and N deposition made no significant contribution to the increases in vegetation productivity. At the provincial scale, each factor explained a part of the variance in NDVI for some provinces, and the increases in NDVI for many provinces could be attributed to the combined effects of multiple factors. Crop yield and PAR were correlated with NDVI for more provinces than were other factors, indicating that both elevated crop yield resulting from improved agricultural management practices and increasing diffuse radiation were more important than other factors in increasing vegetation productivity at the provincial scale. The relative effects of the natural and human factors on vegetation productivity varied with spatial scale. The true contributions of multiple factors can be obscured by the correlation among these variables, and it is essential to examine the contribution of each factor while controlling for other factors. Future changes in climate and human activities will likely have larger influences on vegetation productivity in China
Cartography and diachronic analysis of the vegetation of S'Ena Arrubia Lagoon (Centre-Western Sardinia)
The vegetation map of S'Ena Arrubia Lagoon in centre-western Sardinia (1: 2,500 scale) is presented and some diachronic remarks are made by referring to historical data available. The main object of this cartography, after a research on the biotope vegetation, is to allow the biomonitoring of an extremely important site for the biodiversity conservation (Protected Area: S.I.C., Z.P.S., I.B.A.), which is to use for an ecologically aware management
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