Mulch for landscaping comes in a lot of textures and colors. In some places, hardwood bark is prominent where, in other places, pine straw is the most used mulch. You can even have gravel or cocoa hulls in mulch. These types of mulch help to suppress weeds and conserve moisture. They can do much more too.
First of all, mulch can have a big effect when it comes to solids running off the soil. When the soil is bare, it loses around five times more sediment than when there is mulch on it. This means that mulch helps stop erosion. One thing to note, though, is that using geotextiles (like landscape fabric) under the mulch seems to make the runoff worse. Keep in mind that each kind of mulch absorbs the runoff differently and does not depend on the soil under it to determine the amount of runoff it protects against.
As a temporary forest floor is one way to look at mulch. For consumers, it is a way to suppress weeds, conserve moisture in the soil, and make things look nicer, but it is also a way to help stop erosion. It is great to add to areas where the herbaceous layer or natural leaf litter isn’t available to help the soil hold water and keep it from producing runoffs. In the long run, it helps to improve our quality of water by helping the water to penetrate into the soil rather than flowing into the storm water system. Flowing through the soil also helps to clean the water that we will later use to consume.
So, to recap, mulch brings with it a lot of benefits. It can provide aesthetics, reduce sediment erosion, reduce runoff of water, help to keep the moisture in the soil, and suppress weeds. Generally, plants should fill in the soil whenever possible, even in areas that are covered with mulch. Hopefully more people will become aware of helping the ecosystem by having more natural areas in urban surroundings than paved areas. Mulch allows these areas to stay part of the green infrastructure.