Closed ecosystems, also known as self-sustaining ecosystems, can work in aquaristics under the right conditions. These ecosystems can be created in a sealed environment such as a fish tank, where the balance of plants, animals, and microorganisms can sustain themselves without external inputs. However, maintaining a truly closed ecosystem can be challenging, as it requires careful monitoring and management to ensure that all components are in balance. Additionally, closed ecosystems may not be suitable for all types of aquatic life, and some species may require more specific environmental conditions that cannot be fully replicated in a closed system. **

Germany is home to a variety of ecosystems, including forests, grasslands, wetlands, rivers, lakes, and coastal areas. The country's diverse landscapes support a wide range of plant and animal species, making it a rich and important biodiversity hotspot. These ecosystems are carefully managed and protected through national parks, nature reserves, and conservation efforts to ensure their preservation for future generations. **

Material cycles in ecosystems involve the movement and recycling of essential elements such as carbon, nitrogen, and phosphorus. These elements are taken up by plants from the soil or water, and then transferred to herbivores when they consume the plants. When the herbivores are eaten by carnivores, the elements are further transferred up the food chain. When organisms die, their bodies decompose, releasing the elements back into the environment to be taken up by plants again. This continuous cycling of materials ensures that essential elements are constantly being recycled and made available for use by different organisms in the ecosystem. **

Natural or near-natural ecosystems are areas of land or water that have not been significantly altered by human activity. These ecosystems are characterized by a high degree of biodiversity and are home to a wide variety of plant and animal species. They are often self-sustaining and have complex interactions between different organisms and their environment. Examples of natural or near-natural ecosystems include old-growth forests, coral reefs, and wetlands. These ecosystems are important for maintaining ecological balance and providing essential services such as clean water, air, and habitat for wildlife. **

Streams or rivers are open ecosystems because they are constantly exchanging energy and materials with their surrounding environment. They receive inputs of water, nutrients, and organic matter from the surrounding land, and they also release water and nutrients downstream. This constant flow of materials and energy allows for a high level of biodiversity and dynamic interactions between the organisms and their environment. Additionally, streams and rivers are often connected to other ecosystems such as wetlands, forests, and lakes, further contributing to their open nature. **

One can watch old TV shows online by subscribing to streaming services like Netflix, Hulu, or Amazon Prime Video, which often have a library of older TV shows available for streaming. Another option is to check if the specific TV show is available for purchase or rental on platforms like iTunes, Google Play, or Vudu. Additionally, some TV networks have their own websites or apps where they offer a selection of old TV shows for free with ads. **

Many actors do watch their own TV shows and movies, as it allows them to reflect on their performance and learn from their work. Some actors may find it difficult to watch themselves on screen, while others may enjoy seeing the final product. Ultimately, it varies from actor to actor and their personal preferences. **

There are several ways to watch free movies and TV shows. One option is to use streaming platforms that offer a selection of free content, such as Crackle, Tubi, or Pluto TV. Another option is to check if your local library offers a streaming service that includes movies and TV shows. Additionally, some networks and studios release episodes of their shows for free on their websites or YouTube channels. **