If this is your first pregnancy, you may not feel your baby move until closer to 25 weeks. By the second pregnancy, some women start to feel movements as early as 13 weeks.
exists and is an alternate of. Merge this question into. Split and merge into it. Answer by Mayra03. Confidence votes 145. A landslide or volcanic eruption is a kind of primary disturbance. It causes a very drastic and sudden change in the landscape.ecomposition is not a disturbance of the ecosystem. This is because it is a natural process in harmony with the ecosystem rather than an outside force is interfering.
Primary succession is one of two types of biological and ecological succession of plant life, occurring in an environment in which new substrate devoid of vegetation and other organisms usually lacking soil, such as a lava flow or area left from retreated glacier, is deposited. In other words, it is the gradual growth of an ecosystem over a longer period. In contrast, secondary succession occurs on substrate that previously supported vegetation before an ecological disturbance from smaller thing