03 Describe blan tand its conseque ot nces.
Answers
Answer:
Climate-change scenarios around the world indicate that many areas of the globe will increase in aridity. Thus, all living organisms will suffer from a water scarcity, especially plants, which do not have locomotive structures that allow them to move elsewhere when water and food becomes scarce. As a result, different terrestrial ecosystems (natural and agricultural) will be severely affected and some may even collapse due to the extinction of plant species.
It is therefore important to gain a better understanding regarding the effect of frequent drought stress on biochemical and physiological processes in plants as well as on the plant population and/or community in a particular ecosystem. Despite the negative aspects of such changes, severe environmental conditions can induce interesting adaptations in plants that allow them to survive and reproduce. These adaptations can lead to the emergence of new functional groups in a given ecosystem or serve as an important tool for improving agricultural practices and plant breeding programs.
In recent decades, a large number of investigations have addressed strategies used by plants to control water status, avoid oxidative stress and maintain vital functions in an attempt to understand the morphological and physiological changes plants undergo to ensure their survival under different environmental conditions. Special attention has been given to molecular processes involved in drought tolerance and resistance. While some advances have been made, we still do not fully understand the underlying survival mechanisms in plants due the complex interaction of different forms of stress in natural habitats.
On the ecosystem level, drought induces changes in different processes and frequently demands functional plant responses. Some ecosystems, such as savannas, steppes and scrublands, have intermittent low annual precipitation. In these water-limited ecosystems, drought can seasonally modify carbon and nitrogen cycles, resulting in poor water and mineral uptake by roots, lesser plant growth, a reduction in litter decomposition and the biogenic emission of CO2 from the soil. Severe drought can also induce a higher vegetation mortality rate due to cavitation and/or carbon starvation (reduced photosynthesis and enhanced autotrophic respiration). Thus, more frequent and intense drought periods (and the consequent death of plant species) can alter the phytosociology of entire plant communities over time.
Reductions in aboveground net primary productivity and alterations in functional plant groups are observed in places subjected to prolonged, severe drought. This chapter offers an overview of the effect of drought on individual plants and ecosystems, emphasising aspects of growth, water relations and photosynthesis, especially the electron transport chain, as well as radical oxygen species (ROS) scavenging and its role in avoiding oxidative stress. On the ecosystem level, functional traits commonly associated to water stress tolerance and changes in ecological processes and functional responses in plants will be also discussed.
Answer:
hi
Explanation:
can we be a friend l don't know that answer