You could start by reading Buddhism and environmental issues (which I found, just by doing a Google search for Buddhism environment
and which is intended as an educational resource).
I'veI have read it and I mostly agree with it as a good beginning.
There aren't many right livelihood rules but among them is "Business in poison: producing or trading in any kind of poison or a toxic product designed to kill". I guess that a narrow view of that 'rule' might be that everything is alright except producing chemical warfare agents and pesticides. A much, much broader view might be to minimize 'pollution' of all kinds.
I think there's some justification or precedent for 'interpreting' Buddhism's ethical rules. For example, one of the precepts is literally against "fermented drink that causes heedlessness" but Buddhists today usually understand that as including all "recreational drugs and intoxicating beverages". The earliest Buddhist literature is from 2,500 years ago, which is before various problems of the modern world existed.
Note the second paragraph of "Buddhism and environmental issues": it says, "So, it should certainly not come as a shock to practising Buddhists to discover what environmentalists are now telling us." That's saying that environmentalists know more about the environment, these days, than is taught in Buddhist literature.
So perhaps you can look to Buddhist literature for generalities, or for hints on what attitude to have. I think that's what the Dalai Lama is doing when he gives a speech like this one which includes,
Since I deeply believe that basically human beings are of a gentle nature so I think the human attitude towards our environment should be gentle. Therefore I believe that not only should we keep our relationship with our other fellow human beings very gentle and non-violent, but it is also very important to extend that kind of attitude to the natural environment. I think morally speaking we can think like that and we should all be concerned for our environment.
You can also look for guidance from specific Buddhists if not from Buddhism-in-general.
One of the central doctrines of Buddhism is that things are impermanent. I think it would be wrong, though, to interpret that as "nothing matters" ... to say for example, "Oh let's go ahead and kill on the elephants, what does it matter, everything is impermanent anyway" ... wrong because, as well as breaking the first precept (to avoid killing), there are other important Buddhist values including loving-kindness and compassion.
There are a few more things I think that maybe you could want to know.
- The quantity of Buddhist literature is vast. So your question, "what do buddhists religious texts say about the environment?" is a little bit like asking, "What do English-language scientific texts say about the environment?", i.e. it's difficult to summarize
- Most of Buddhist literature focuses on topics other than 'the environment'.
- There are several schools of Buddhism (like there are many schools of Christianity). If you want to ask another question, one way to narrow it down would be to say whether you interested in the literature from a specific school, or from a specific time period: e.g. modern literature; medieval literature; or the earliest literature, the Pāli Canon which is from about 2000 years ago.
- There are separate (and stricter or more numerous) rules of behaviour for Buddhist monks: which are called the Vinaya. There's a bit of a symbiotic relationship between Buddhist monks and laypeople, for example monks shouldn't work for a living (shouldn't handle money) and laypeople should support them with gifts of food and other essentials (basically just food, a robe to wear, medicine when needed, and maybe a place to live). Someone who is living a monk's life (and a lot of Buddhist literature is by and perhaps for monks) might be unlikely to have a huge, negative environmental impact. This explanation of the Vinaya rules on Harmlessness says,
Throughout its history Buddhism has been renowned for its tolerance and compassion towards all living beings and this is reflected in the Buddhist monks' Vinaya. Their rules cover situations of causing harm ranging from murder — which is universally accepted as a crime — to such things as destroying plant life.
Rules against destroying vegetation include even digging the ground...
- When the historical Buddha lived and taught (2400 years ago) there were other religions ... which the Buddha probably learned before his enlightenment. One of these is called Jainism. I mention Jainism because it's practice of Amhisa (non-violence) is similar to or stricter than Buddhism's, even for laypeople; and because Jainism and Buddhism may have influenced each other, to some extent, historically.