62 IACHR has characterized the illegal invasions and intrusions of non-indigenous persons as threats, usurpations, and reductions of the rights to property and effective possession of the territory by 328 indigenous and tribal peoples that the State is obligated to control and prevent. 231. In addition, the case-law of the inter-American human rights system on indigenous peoples’ right to communal property has explicitly incorporated within the material scope of this right the natural resources traditionally used by the indigenous peoples and bound up with their cultures, including for spiritual or cultural uses. In this respect, the Inter-American Court has indicated: [T]he right to use and enjoy their territory would be meaningless in the context of indigenous and tribal communities if said right were not connected to the natural resources that lie on and within the land. That is, the demand for collective land ownership by members of indigenous and tribal peoples derives from the need to ensure the security and permanence of their control and use of 329 the natural resources, which in turn maintains their very way of life. 232. According to the case-law of the Inter-American Court, “members of tribal and indigenous communities have the right to own the natural resources they have traditionally used within their territory for the same reasons that they have a right to own the land they have traditionally used and occupied for 330 centuries. Without them, the very physical and cultural survival of such peoples is at stake.” Accordingly, the right of indigenous peoples to property over, access to, and the use of the natural resources present in their traditional territories is closely bound up with the survival of the indigenous peoples as differentiated peoples, mindful of aspects that go to both their material sustenance and their cultural survival. As the Court has affirmed, this connection between the territory and the natural resources that the indigenous and tribal peoples have traditionally used and that are necessary for their physical and cultural survival, as well as the development and continuity of their cosmovision, must be protected under Article 21 of the Convention to guarantee that they can continue their traditional way of life and that their cultural identity, social structure, economic system, customs, beliefs, and distinct 331 traditions will be respect, ensured, and protected by the states. 233. In addition, although neither the American Declaration of the Rights and Duties of Man nor the American Convention on Human Rights includes any express reference to the protection of the environment, it is clear that several fundamental rights enshrined therein require, as a precondition for their proper exercise, a minimal environmental quality, and suffer a profound detrimental impact from the degradation of the natural resource base. The IACHR has emphasized in this regard that there is a direct relationship between the physical environment in which persons live and the rights to life, security, and 328 IACHR, Report on the Situation of Human Rights in Brazil. Doc. OEA/Ser.L/V/II.97, Doc. 29 rev. 1, September 29, 1997, Chapter VI, paras. 33, 40. IACHR, Indigenous and Tribal Peoples’ Rights over their Ancestral Lands and Natural Resources: Norms and Jurisprudence of the Inter-American Human Rights System. OEA/Ser.L/V/II.Doc.56/09, December 30, 2009, para. 114. 329 I/A Court H.R., Case of the Saramaka People v. Suriname. Preliminary Objections, Merits, Reparations and Costs. Judgment of November 28, 2007. Series C No. 172. I/A Court H.R., Case of the Yakye Axa Indigenous Community v. Paraguay. Merits, Reparations and Costs. Judgment of June 17, 2005. Series C No. 125, paras. 124, 137. I/A Court H.R., Case of the Sawhoyamaxa Indigenous Community v. Paraguay. Merits, Reparations and Costs. Judgment of March 29, 2006. Series C No. 146, paras. 118, 121. I/A Court H.R., Case of Kichwa Indigenous People of Sarayaku v. Ecuador. Merits and Reparations. Judgment of June 27, 2012. Series C No. 245. para. 146. 330 I/A Court H.R., Case of the Saramaka People v. Suriname. Preliminary Objections, Merits, Reparations and Costs. Judgment of November 28, 2007. Series C No. 172. para. 121. See also: I/A Court H.R., Case of the Yakye Axa Indigenous Community v. Paraguay. Merits, Reparations and Costs. Judgment of June 17, 2005. Series C No. 125, para. 137. I/A Court H.R., Case of the Sawhoyamaxa Indigenous Community v. Paraguay. Merits, Reparations and Costs. Judgment of March 29, 2006. Series C No. 146, para. 118. I/A Court H.R., Case of Kichwa Indigenous People of Sarayaku v. Ecuador. Merits and Reparations. Judgment of June 27, 2012. Series C No. 245. para. 147. 331 I/A Court H.R. Case of Kichwa Indigenous People of Sarayaku v. Ecuador. Merits and Reparations. Judgment of June 27, 2012. Series C No. 245. para. 146. See also: I/A Court H.R., Case of the Yakye Axa Indigenous Community v. Paraguay. Merits, Reparations and Costs. Judgment of June 17, 2005. Series C No. 125, paras. 125 and 135. I/A Court H.R., Case of the Sawhoyamaxa Indigenous Community v. Paraguay. Merits, Reparations and Costs. Judgment of March 29, 2006. Series C No. 146, paras. 18 and 21.