The concept of 'environmental resilience' has gained traction in ecological studies, referring to an ecosystem's capacity to absorb disturbances while maintaining its fundamental structure and functions. Recent research suggests that resilience is not a static property but a dynamic process influenced by biodiversity. Higher species diversity often enhances functional redundancy, where multiple species perform similar roles, ensuring that ecosystem processes continue even if some species decline. However, critics argue that focusing solely on diversity overlooks the impact of keystone species, whose removal can trigger cascading effects disproportionate to their abundance. Moreover, resilience thresholds are difficult to predict due to nonlinear responses to stressors like climate change. A study by Thompson et al. (2022) demonstrated that temperate forests with mixed tree species recovered faster from drought than monocultures, yet they warned that such benefits diminish under extreme, repeated disturbances. Thus, while biodiversity is a buffer, it is not a panacea, and adaptive management strategies must account for uncertainty.
❓ Согласно тексту, в чём заключается ограничение reliance на биоразнообразие для обеспечения устойчивости экосистем?
A. A. Биоразнообразие приносит пользу только лесам умеренного пояса, а не другим экосистемам.
B. B. Функциональная избыточность не имеет значения, когда присутствуют ключевые виды.
C. C. Защитный эффект биоразнообразия может ослабевать при серьёзных или повторяющихся нарушениях.
D. D. Пороговые значения устойчивости всегда предсказуемы и поэтому не требуют адаптивного управления.
✅ 正确答案
C. The protective effect of biodiversity may weaken under severe or repeated disturbances.
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