The Ecology and Management of Wood in World Rivers

2003 ◽  
Keyword(s):  
Land Use ◽  
Land Use Changes ◽  
Livestock Grazing ◽  
Wood Structures ◽  
Groundwater Levels ◽  
Stream Discharge ◽  
Small Streams ◽  
World Rivers ◽  
Beaver Dams ◽  
Stream Systems

<em>Abstract.</em>—Beaver dams alter the hydrology and geomorphology of stream systems and affect habitat for fishes. Beaver dams measurably affect the rates of groundwater recharge and stream discharge, retain enough sediment to cause measurable changes in valley floor morphology, and generally enhance stream habitat quality for many fishes. Historically, beaver dams were numerous in small streams throughout most of the Northern Hemisphere. The cumulative loss of millions of beaver dams has dramatically affected the hydrology and sediment dynamics of stream systems. Assessing the cumulative hydrologic and geomorphic effects of depleting these millions of wood structures from small and medium-sized streams is urgently needed. This is particularly important in semiarid climates, where the widespread removal of beaver dams may have exacerbated effects of other land use changes, such as livestock grazing, to accelerate incision and the subsequent lowering of groundwater levels and drying of streams.

Generating Policies for Sustainable Water Use in Complex Scenarios: An Integrated Land-Use and Water-Use Model of Monroe County, Michigan

2007 ◽  
Vol 34 (4) ◽  
pp. 664-686 ◽  
Author(s):  
Moira L Zellner
Keyword(s):  
Land Use ◽  
Water Use ◽  
Land Use Changes ◽  
Resource Depletion ◽  
Analytical Framework ◽  
Monroe County ◽  
Land Use Patterns ◽  
Groundwater Levels ◽  
Use Patterns ◽  
Water Users

Rapidly declining groundwater levels since the early 1990s have raised serious concern in Monroe County, Michigan. Hydrological studies suggest that land-use changes have caused this decline. The mechanisms linking land-use and groundwater dynamics are not clear, however. In this paper I present WULUM, the Water-Use and Land-Use Model, an agent-based model that serves as an analytical framework to understand how these processes interact to create the observed patterns of resource depletion, and to suggest policies to reverse the process. The land-use component includes the main groundwater extractors in the county—stone quarries, golf courses, farms, and households. The groundwater component includes the glacial deposits and the underlying bedrock acquifer. The behavior of water users is defined by simple rules that determine their location and consumption. The dynamics of groundwater are represented through infiltration and diffusion rules between each cell and its immediate neighbors. Initial explorations with the model showed that land-use patterns contributed significantly to groundwater declines, while eliminating quarry dewatering did not entirely solve the problem. Both low-density and high-density zoning restrictions improved aquifer conditions over medium-density development, suggesting a nonlinear relationship between intensity of residential use and groundwater levels. Moreover, of all the natural and policy variables, zoning had the greatest influence on urban settlement and therefore on resource consumption.

Land-use and Threats to Parks in the Neotropics

1989 ◽  
Vol 16 (1) ◽  
pp. 13-18 ◽  
Author(s):  
Roderick P. Neumann ◽  
Gary E. Machlis
Keyword(s):  
Land Use ◽  
Statistical Analysis ◽  
National Parks ◽  
Conservation Biology ◽  
National Park ◽  
Land Use Changes ◽  
Livestock Grazing ◽  
Park Management ◽  
Land Uses ◽  
Political Economic

The ecological consequences of contemporary land-use in the neotropics have important influences on national park management in the region. Historical patterns suggest that major land-use changes have occurred regularly, and that these patterns have recently intensified. Is there a relationship between specific land-uses and specific threats to protected areas? Can this relationship be detected in a population of parks?In a survey of managers of 183 national parks, 122 returned questionnaires from 19 countries in the neotropics. We found that a range of land-uses, from livestock grazing to quarrying, are occurring in and around the parks. The results of our statistical analysis indicate that many of these activities are associated with specific threats to park resources: for example, poaching for subsistence was statistically associated with each of the ten most-reported threats.We offer two suggestions for improving our understanding of environmental degradation within parks. First, that research and park management be expanded to acquire a regional focus, namely that the land-transforming activities which threaten park resources can best be understood by incorporating the regional-social and political-economic contexts in the analysis. Second, that the influences of the global economic system be increasingly considered in conceptual frameworks of conservation biology.

scholarly journals Land subsidence in the San Joaquin Valley, California, USA, 2007–2014

2015 ◽  
Vol 372 ◽  
pp. 23-27 ◽  
Author(s):  
M. Sneed ◽  
J. T. Brandt
Keyword(s):  
Land Use ◽  
Surface Water ◽  
Land Subsidence ◽  
Groundwater Level ◽  
Land Surface ◽  
Land Use Changes ◽  
San Joaquin Valley ◽  
Flood Hazards ◽  
Groundwater Levels ◽  
Measured Rate

Abstract. Rapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater pumping, groundwater-level declines, and land subsidence. Differential land subsidence has reduced the flow capacity of water-conveyance systems in these areas, exacerbating flood hazards and affecting the delivery of irrigation water. Vertical land-surface changes during 2007–2014 were determined by using Interferometric Synthetic Aperture Radar (InSAR), Continuous Global Positioning System (CGPS), and extensometer data. Results of the InSAR analysis indicate that about 7600 km2 subsided 50–540 mm during 2008–2010; CGPS and extensometer data indicate that these rates continued or accelerated through December 2014. The maximum InSAR-measured rate of 270 mm yr−1 occurred in the El Nido area, and is among the largest rates ever measured in the SJV. In the Pixley area, the maximum InSAR-measured rate during 2008–2010 was 90 mm yr−1. Groundwater was an important part of the water supply in both areas, and pumping increased when land use changed or when surface water was less available. This increased pumping caused groundwater-level declines to near or below historical lows during the drought periods 2007–2009 and 2012–present. Long-term groundwater-level and land-subsidence monitoring in the SJV is critical for understanding the interconnection of land use, groundwater levels, and subsidence, and evaluating management strategies that help mitigate subsidence hazards to infrastructure while optimizing water supplies.

Public Land Acquisition and Land Use Change Problems in Ogun State

2015 ◽  
Vol 2 (8) ◽  
pp. 34-41
Author(s):  
Bello Ismail K ◽  
Sodiya Abiodun K ◽  
Solanke Peter A
Keyword(s):  
Land Use ◽  
Land Use Changes ◽  
Global Environmental Change ◽  
Livestock Grazing ◽  
Urban Centers ◽  
Ogun State ◽  
Global Environmental ◽  
Determining Factors ◽  
Human Use ◽  
Policies And Programs

Human use of land has altered the structure and functioning of ecosystem. The most spatially and economically important human uses of land globally include cultivation in various forms; livestock grazing, settlement and construction, reserves and protected lands and timber extraction. The patterns of land use give us insight into the factors that have caused the land cover to change. A better understanding of the determining factors of land use changes is of crucial importance to the study of global environmental change. This paper theoretically strive to evaluate the contributions of government policies and programmes in transforming the various land uses in the urban centers of Ogun state with a view to provide better understanding among the stakeholders in real estate investment. The paper recommended that although landuse changes is an inevitable consequences in the developing nations, there is the need to consider the positive and negative aspect of the policies in order not to jeopardize the available environmental resources for sustainable development. The paper concluded by emphasized the need for government to carry the citizen along in the various policies and programs for even development.

Effect of changing groundwater levels caused by land-use changes on greenhouse gas fluxes from tropical peat lands

2005 ◽  
Vol 71 (1) ◽  
pp. 81-91 ◽  
Author(s):  
Yuichiro Furukawa ◽  
Kazuyuki Inubushi ◽  
Mochamad Ali ◽  
A. M. Itang ◽  
Haruo Tsuruta
Keyword(s):  
Land Use ◽  
Greenhouse Gas ◽  
Land Use Changes ◽  
Groundwater Levels ◽  
Tropical Peat ◽  
Gas Fluxes ◽  
Greenhouse Gas Fluxes

scholarly journals UNDERSTANDING COMMUNITY PERCEPTIONS OF LAND USE CHANGES IN THE RANGELANDS, ZIMBABWE

2011 ◽  
Vol 47 (S1) ◽  
pp. 153-168 ◽  
Author(s):  
ANDREW SIBANDA ◽  
SABINE HOMANN-KEE TUI ◽  
ANDRÉ VAN ROOYEN ◽  
JOHN DIMES ◽  
DANIEL NKOMBONI ◽  
...  
Keyword(s):  
Land Use ◽  
Water Productivity ◽  
Land Use Changes ◽  
Dry Season ◽  
Livestock Grazing ◽  
Household Food Security ◽  
Community Perceptions ◽  
Feed Resources ◽  
Livestock Feed ◽  
User Communities

SUMMARYThe objective of this study was to investigate the user communities' understanding and interpretation of changes in rangeland use and productivity in the communal lands of Zimbabwe. While external knowledge has been instrumental in defining the drivers and effects of ecological changes hitherto, the role of local knowledge is becoming increasingly important in explaining factors that inform user community perceptions and guide their decisions on the use of rangeland resources. Data on community perceptions were collected in four villages, using Participatory Rural Appraisals in each village and household surveys with a total of 104 households. This study showed that user communities in Nkayi district differentiate rangelands among seven categories of livestock feed resources and how these have changed over time. Communities viewed rangelands not as one continuous, designated and specialized land parcel, but differentiated the land by location, productivity, management and uses in different times of the year. Although land use changes affecting these livestock feed resources were considered to be widespread and multi-directional (both negative and positive) they did not cause widespread degradation. Rangelands converted to croplands were not completely lost, but became important dual purpose land parcels fulfilling both household food security needs and dry season livestock feed requirements. The importance of croplands as a feed resource is reflected in the emergence of new institutions governing their use for livestock grazing and to guarantee security of tenure. On the other hand institutions governing the use of common property rangelands decreased or weakened in their application. The study concludes that while this situation presents ecological challenges for the rangelands, it offers opportunities to find innovative ways of utilizing croplands as the new frontier in the provision of dry season feed resources to smallholder farmers in highly variable environments. Implications for livestock water productivity need to be investigated and water saving technologies should be promoted in the land use intensification processes.

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