Can someone read over this paragraph and tell me if I should add anything? thanks. My terrarium has a geosphere (my plant and soil) , biosphere (oxygen) , hydrosphere (the water I used to feed my plant) , and finally, my atmosphere (an LED plant light) .
These are the things my plant needs to survive.

Remove the 'my' in the sentences, basically if you want it to be grammatically correct rewrite like this:

The terrarium that was built has a geosphere, the plants and soil, an atmosphere, the oxygen that allows the life to grow, a hydrosphere, the water the plant uses, and finally a source of light. Overall this makes a biosphere which allows the plant to survive and thrive.

Also you mixed up biosphere with the atmosphere.

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.