The theme for world Environment day 2021 is “Ecosystem Restoration” and will also see the launch of UN Decade of Ecosystem Restoration-2021 to 2031. It would be the best time to understand the concept of ecosystem and its restoration. Ecosystem is a dynamic, self-sustaining unit where living organisms interact with each other and with their physical environment in a given area. The ecosystems are basic functional units of a biosphere. Biosphere is a region including parts of lithosphere, atmosphere and hydrosphere where life could be found. It implies biosphere is part of the planet earth which is favourable for life to survive and thrive. Ecosystems being dynamic in nature keep changing over time. The changes could be due to natural factors or anthropogenic factors. The ecosystems which are untouched by humans would too change over time. Studying the patterns of change in ecosystems dein response to natural or human disturbance is an important tool for learning how to restore the damaged ecosystems. The classical process of change of ecosystems over time is reffered to as succesion or ecological succession. This is sometimes referred to as ecosystem development. The pocess of succession starts on the areas which are disturbed due to some factors and hence are not in equilibrium. The succession culminates when the area becomes stable and is in equilibrium with the environmental factors. Now there is no scope for improvement. These stable stages could be forest ecosystems, grasslands, deserts etc. depending on the aggregate of edaphic and climatic factors. Humans are managing ecosystems as per their requirement. Humans sometimes keeps the ecosystems from reaching the climax stage ( The most stable state of the ecosystem where edaphic and climatic factors are in equilibrium). As the stages before the climax are more beneficial to them, as it is providing them some material goods. Such a stage is called dis-climax( disturbed climax), this became more or less stabilised due to recurrent disturbances by man or other biotic factors, which prevent the establishment of climax community in the area. At same place, under similar climatic conditions, if the disturbances are removed, there would develop different communities which would be the climax community of the area under natural conditions. The human made or managed ecosystems are a dis-climax community. We, humans have moved from being a part of the nature to being apart from the nature. We may not say that. But our activities tell that loud and clear. We have started over-utilization of the resources provided by the nature. The product of this over-utilization of resources is pollution. We have pollutants now everywhere. We don’t have the places to dump our pollutants properly. So we are dumping them whereever we are finding any open space, for that seems cheap and easy way. So we have dumped them in the nearby ecosystems which has hampered their self-sustaining ability and the succession has started in backward direction, commonly called retrogressive succession. In simpler terms, it is going from bad to worse as far as the ecosystem is concerned. The above factors have lead to ecosystem degradation.
The practices of afforestation and reforestation are different in a way that they are just the practice of planting some sapling. Which results in reduced resilence and biodiversity. Further it causes major alterations in the structure and composition of an ecosystem. Hence, Restored sites are always close to the nature, having good resilience and rich biodiversity.
Ecosystem degradation is one of the biggest environmental threats that has emerged in last few decades. All the ecosystems- terrestrial and aquatic have undergone some amount of degradation. The causes of the ecosystem degradation are cheifly human induced, like Dumping of solid wastes, cutting down of the forests. Developmental projects, introduction of alien species, excessive use of fertilizers, climate change etc. Ecosystem degradation is affecting both the diversity of the species and also ecological services provided by the ecosystems. The ecological services provided by ecosystems are mostly under-appreciated. Many biodiversity rich areas are under great threat due to degradation of the ecosystems. The ecosystems have got some ability to recover itself from the damages and injures caused to it due to different factors. Many ecosystems are damaged to such an extent, that they won’t be able to self- recover. In hilly areas, most of the ecosystems are fragile and small amount of disturbances or pressures could take them to some other equilibrium state. Traditional approaches of conservation focussing on protection and making natural places out of reach of human interference and allowing them into heal on its own won’t be sufficient now. The recovery of the ecosystem has to assisted. This approach of assisting the recovery of ecosystem that has been degraded, damaged or destroyed etc is reffered to as ecosystem Restoration. The ecosystem is recovered to predegradation stage or close to it. This is done by keeping similar native ecosystem as a reference. The key structural and species characteristics are similar to that of the native ecosystem, the group to which it belongs to. Restoration practioners assist recovery by making conditions favourable for plants, animals and micro-organisms, so that they would carry out the work of recovery themselves. This could be just the re-introduction of some native species or removal of some alien species. The restoration of ecosystem of Yellow Stone National Park, USA was successfully done by re- introduction of wolves in it. The goal of ecological restoration is to return to the historic trajectory of the ecosystem. The ecosystem would not return to back to its former state owing to ecological realities and climatic change. It may develop along an altered trajectory, as would be the case with native ecosystems which are undisturbed due contemporary conditions. Restoration adopts a holistic approach which takes into consideration the flora, fauna, hydrology, soil factors etc of an ecosystem. This enhances the regenerative capacity of an ecosystem. The practices of afforestation and reforestation are different in a way that they are just the practice of planting some sapling. Which results in reduced resilence and biodiversity. Further it causes major alterations in the structure and composition of an ecosystem. Hence, Restored sites are always close to the nature, having good resilience and rich biodiversity.
(The author is Lecturer (EVS) at Govt Degree College Kupwara, Views are his own)
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