Channelized Stream

Here are some sad photos of a channelized stream in Pickering, Ontario that I had the pleasure of interacting with at a summer job with the TRCA.

Colleen did such a good job with her presentation. I wanted to read up more on Rivers.

And here is what I found on the net with regards to


Riffle and Pool Pictures and Diagrams

Cool River Pattern

Here's a pretty interesting river pattern I found in Mali, in the west part of Africa:

Good Landcape Ecology Concise Definition
and Conceptual Diagram

Source: http://www.k-state.edu/withlab/landecol/

What is Landscape Ecology? Landscape Ecology is a rapidly emerging discipline concerned with the study of the effects of spatial pattern on ecological process. All ecological systems possess spatial complexity at some scale, and thus Landscape Ecology is applicable to all areas of ecology encompassing a wide range of scales (from fine scales to broad regional scales), systems (both terrestrial and aquatic), and disciplines. Ecology has traditionally either ignored spatial complexity or has focused on how ecological processes give rise to spatial pattern. Landscape Ecology thus provides a complementary approach, by explicitly focusing on how spatial pattern affects ecological process. Landscape Ecology is becoming increasingly relevant for applied areas of ecology, such as conservation biology, ecological restoration, biological control, invasive species biology, and ecosystem management. Happy Reading Week!! RAZA

Oxbows on the Mississippi

Hey again,

Here's a neat shot of an oxbow lake in formation on the Mississippi...What's even more interesting is that the river diverted to a new path after an earthquake in the late 1800's. New decisions about how to divide states had to be made at this time (previously, they were divided by the middle of the river channel). The white lines show these state divisions. As you can see, the 'Kentucky Loop' as it's called (the peninsula jutting out with the river almost completely surrounding it), is actually a part of Kentucky (the state in the top-right of the shot), and is completely cut off from it! Tennessee is to the bottom right, Missouri takes up the left part of the shot. If you follow the white state lines up and down the river, you can see how the historical position of the river has been preserved, and parts of states get cut off from each other quite frequently (there are actually two more examples of this at the extreme top of the picture too!)

Oxbows are fun...

Eric

Raza Posted the previous blog.

Hey all I fogot to include my name.

Hey Class, I found the following Landscape Ecology Definitions & Principles from this site below: http://www.class.uidaho.edu/italy2004/ecology2.htm.

The material is concise and the photos are helpful as well.

Have a good reading week.

Land Mosaics
Turin, Italy	The landscape is really a mosaic of elements arranged spatially. This mosaic as illustrated by the image above is composed of a pattern of patches and corridors within a more or less uniform matrix. Since this mosaic is spatial there are important implications for land use planning. Urban development also results in a spatial mosaic of nodes and corridors within a matrix of residential housing.
Patches
Clear cut slope	Patches area landscape units that are naturally occurring or defined by man. Often they are remnants of forest fire or other natural process. Increasingly they are the places left after human modification. Patches are wildlife and environmental resources. Since man has demonstrated a great capacity to destroy natural areas in the acquisition of natural resources or space for development it makes sense that man could configure patches that remain after destruction of areas around them.
Patch Differentiation
(Corel)	The size, number and location of patches is critical in the provision of habitat for wildlife and plan communities.
Size and Species
(Dramstead)	The top image illustrates two kinds of habitat in a patch. The interior of the patch supports some species that the edge of the patch doe not. As patches become smaller the amount of edge habitat increases relative to interior habitat. Size of patches is related to the chance of extinction and to the amount of habitat diversity within the patch. Some organisms require large patches to acquire all the food they need. Examples, of these large home range animals are bear, mountain lion, and elk. Large patches are also necessary when protection of aquifers or stream networks is important. Of course, the quality of the habitat is important. The third diagram illustrates that the same number and diversity of organisms may be present in a small high quality patch as in a large low quality patch. The image below shows small patches of evergreen woodland within a grassland matrix. (Corel)
(Dramstead)	Fractal patches Many small patches do not offer the same habitat opportunity as a single larger patch, especially for organisms that require interior habitat.
Patch Relationships
(Corel)	The spatial relationship of patches determines the degree of isolation of population groups and the threat of extinction. The opportunity for reconinization of habitat is another factor influenced by the relationship of patches to each other. When selecting land areas for conservation, as part of a planned unit development for example, the distance between patches and the shape of the patches can enhance the value of the habitat conserved.
Edges and Boundaries
(Corel)	Since patches, corridors and the matrix itself are spatial elements the designer can manipulate the configuration of them to maximize the benefit.
	Administrative versus ecological edge. A land area boundary determined by jurisdiction or property ownership generally lacks the complexity of an ecologically produced habitat boundary. However, a political boundary can protect habitat by isolating it from public use.
	While generally undesirable, gaps in patches can prevent the spread of some kinds of disturbance such as fire.
	Edge abruptness tends to reduce habitat diversity.
	The patch edge acts as a filter to reduce the negative impact of some kinds of disturbance such as noise or air born pollutants such as pesticides.
	Straight patch edges offer fewer niche habitat opportunity than curved edges
	Windward side of patch has a wider edge zone since disturbance is greater from wind and snow.
(Dramstead)	Convoluted edges provids predator and prey sites, as well as migration points. Enlarge this image to study the relationship of locations along the edge. (Corel)
Ecosystem Measurements
(Corel)	The measure of healthy and sustainable ecosystems incldes positive physical structure, ecological functions and change. Ecosystems have both vertical and horizontal structure. Generally the greater the variety in vertical stratification and horizontal distribution of plant and animal communities the greater the health and stability of the ecosystem. Resistance to change and resiliance after change are measures of ecosystem health.

Corridors

Click on the thumbnails for a larger image	(Corel)
(Dramstead)	Corridors perform five major functions. 1. habitat 2. conduit 3. filter 4. source and 5. sink. Corridor continuity and width are the two primary determinates of how well the five corridor functions are realized. (Corel)
(Dramstead) (Corel)	Some species have wide ranging territories. They will be hindered less by wider gaps in the corridor than species with more limited territories. When the contrast between the material of the corridor and the material of the matrix is high, the effectiveness of the corridor is compromised.
Patch and Corridor Networks
	Small patches or nodes in a network provide good habitat. The dispersal of offspring is facilitated by the network of corridors.
	The intersections of corridors of natural vegetation typically contain more interior species and higher diversity of plants and wildlife than the rest of the corridor.
	Loops and alternative routes compensate for gaps in the corridors, disturbances, predators and hunters.
	When there is more complexity within the network of patches and corridors, species movement is enhanced.
	This bridge is an example of a design that breaks a corridor. It places a barrier in a wildlife corridor.
(Dramstead)	This is a better design for wildlife since one bay of the bri