What is Ecological succession? How Hydrarch succession is different from Xerarch succession?

The ecological succession can be defined as the changes in the ecological community over a particular area. The change results in the alteration of the fauna and flora composition. The succession can result in the initiation of pioneer succession, serial, and climax community succession. Characteristics Hydrarch succession Xerarch succession Definition Hydrarch succession occurs in the population of terrestrial plants that need high water requirements. For example, phytoplanktons and Vallisneria grow more efficiently in the water. A xerarch succession can be characterised as a form of plant succession starting in the bare ground that is very dry or is limited by the availability of water, and eventually culminating in a mature forest. Such communities usually originate from extremely dry environments such as rock deserts and sand dunes.

Write a short note on ecosystem services.

An ecosystem is a community of lifeforms where biotic and abiotic factors interact with each other. Healthy ecosystem forms the base for a wide range of economic, environmental, and aesthetic goods and services. The product of ecosystem processes are named as ecosystem services. For example, in a healthy forest ecosystem, it purifies air and water, nutrient cycling that includes both gaseous and sedimentary cycles. It generates fertile soils, provides wildlife habitat, maintains biodiversity, storage site of carbon. It also provides aesthetic, cultural and spiritual values.

Describe three factors which affect on decomposition.

Decomposition is also regarded as the disintegration or rupture of complex organic matter into simpler inorganic matter. It is one of the significant and essential processes of the ecosystem. The three factors that affect decomposition are: In a particular climatic condition, the decomposition rate is slower if detritus is rich in lignin and chitin and quicker, if detritus is rich in nitrogen and water-soluble substances like sugars. Temperature and soil moisture are the most important climatic factors that regulate decomposition through their effects on the activities of soil microbes. Warm and moist environment favour decomposition whereas low temperature inhibits decomposition resulting in the build-up of organic materials.

Name the type of food chain that is the major conduit for energy flow in an aquatic ecosystem.

GFC or Grazing food chain starts at the producer level and ends on secondary or tertiary consumer and is the chief energy transfer form. DFC or Detritus food chain is the chain that begins with detritivores or decomposers. In an aquatic ecosystem, GFC is the main conduit of energy because it is the chief form of energy transfer where the chain begins with the primary producers like phytoplankton, which are eaten by the zooplanktons. The zooplankton is eaten by different fishes which are eaten by bigger fishes or birds like Pelicans or Cranes.