sentences: cutting down trees has a negative impact on an ecosystem / organisms living in an ecosystem & logging is when humans cut down trees / forests for wood ->  logging has a negative impact on the ecosystem  logging has a negative impact on the ecosystem & surface mining has a negative impact on the lithosphere / the biosphere / the ecosystem ->  surface mining and logging have negative impacts on the ecosystem  killing means harming something causing death & harming an animal species has a negative impact on the population size of that species ->  killing an animal has a negative impact on that animal's population  killing an animal has a negative impact on that animal's population & cutting down trees has a negative impact on an ecosystem / organisms living in an ecosystem0 ->  hunting has a negative impact on animal populations  an animal is a kind of organism & organisms are a part of an environment ->  animals are a part of the environment  animals are a part of the environment & ecosystem can mean environment ->  animals are a part of the ecosystem  hunting has a negative impact on animal populations & animals are a part of the ecosystem ->  hunting has a negative impact on the ecosystem  surface mining and logging have negative impacts on the ecosystem & hunting has a negative impact on the ecosystem ->  surface mining and logging and hunting have negative impacts on the ecosystem  surface mining and logging and hunting have negative impacts on the ecosystem & cutting down trees has a negative impact on an ecosystem / organisms living in an ecosystem1 ->  limiting mining and logging and hunting has a positive impact on the ecosystem  limiting mining and logging and hunting has a positive impact on the ecosystem & national parks limit mining / logging / hunting -> national parks have a positive impact on the ecosystem by limiting mining and logging and hunting