Wigeongrass Ruppia Maritima L

There is a growing need for appropriate management of aquatic plants in rivers and canals, lakes and reservoirs, and drainage channels and urban waterways. This management must be based on a sound knowledge of the ecology of freshwater plants, their distribution and the different forms of control available including chemical and physical, and biological and biomanipulation. This series of papers from over 20 different countries was generated from the tenth in the highly successful series of European Weed Research Society symposia on aquatic plant management, this being the tenth. It provides a valuable insight into the complexities involved in managing aquatic systems, discusses state-of-the-art control techniques and deals with patterns of regrowth and recovery post-management. Careful consideration is given to the use of chemicals, a practice which has come under scrutiny in recent years. Underpinning the development of such control techniques is a growing body of knowledge relating to the biology and ecology of water plants. The authorship of the papers represents the collective wisdom of leading scientists and experts from fisheries agencies, river authorities, nature conservation agencies, the agrochemical industry and both governmental and non-governmental organisations.

This work is a scientific monograph that examines the flora and vegetation of natural mineral wetlands in comparison to mineral wetlands affected by bitumen exploitation. The work is of broad relevance because (a) wetland loss and degradation is a global problem; (b) the continued global increase in fossil fuel exploitation is resulting in widespread damage; and (c) bitumen (tar sands, oil sands) exploitation is a rapidly growing and destructive set of activities. The core of the work is a meta-analysis of 417 vegetation plots. Analyses of change over time and chemical and physical attributes of water and soil are presented for the subset of plots with sufficient data. The purpose of the work is to demonstrate that: (1) There are marked differences between natural and industrially-affected wetlands. (2) Industrially-affected mineral wetlands differ from natural wetlands in their vegetation assemblages, their depressed vegetation and species diversity, and their abundance of exotic weeds. (3) Successful post-bitumen mining wetland reclamation has not been accomplished and may not be attainable within the foreseeable future given the ecological and physical conditions of the industrial wetlands, current reclamation practices, and lax regulatory standards. In regard to government policy and industrial practices, it finds that they are responsible for reclamation failure on a grand scale.

Describing the natural state of eight important lakes in Asia and the human impact on these lake ecosystems, this book offers a valuable reference guide. Over the past several decades the Aral Sea, Dead Sea, Lake Balkhash and other major lakes in Asia have undergone significant changes with regard to their size, water level, chemical composition, and flora and fauna. Most of these changes resulted from the loss of water from tributaries (now used for irrigation farming) or increasing consumption in local industries and households. However, significant human impacts may have begun as early as 2000 years ago. In addition to the three lakes mentioned above, Lake Sevan (Armenia), the Caspian Sea (Azerbaijan, Iran, Kazakhstan, Russia, Turkmenistan), Lake Issyk-Kul (Kyrgyzstan), and Lake Lop Nur (China) are discussed as the most prominent examples of changing lake ecosystems. In contrast, an example of an almost pristine lake ecosystem is included with the report on Lake Uvs Nuur (Mongolia). For each lake, the book summarizes its origin and early geological history, and reconstructs its natural state and variability on the basis of proxy records from drilled or exposed lake sediments that have accumulated since the last ice age. The frequently observed reductions in lake level and size during most recent decades led often to significant environmental impacts in the respective lake catchments including vegetation deterioration, soil erosion and badland formation, soil salinization or the formation of sinkholes.