Street Broad Scientific
Essay
Effects of Climate Change on Agriculture Matias Horst and Vivek Pisharody Without a doubt, global climate change presents a serious threat to agricultural productivity. Current data indicate that immediate, directed action is necessary to protect world food security. Unfortunately, political conlicts regarding climate change have hindered the development of solutions to these issues. However, there are numerous innovative methods that have been proposed to combat the negative impacts of climate change on agriculture regardless of international unwillingness to address the problem itself. Agriculture is perhaps the single human activity most closely tied to climate. However, evaluating the impact of global climate change on agriculture presents a diiculty in that while climate change occurs on the global scale, impacts on agriculture occur at the local level, with considerable variation between diferent regions. In their analysis, Kurukulasuriya and Rosenthal predict a modest net decrease in world agricultural output. Decreased yields in some regions will slightly outweigh productivity gains in other regions. However, the real threat to world food security arises not from this net decrease, but from the distribution of climate related efects on agriculture [1]. he true challenge of dealing with climate change’s efects on agriculture lies in tailoring unique solutions to speciic regions and their respective climates. In many areas, climate change has already reduced agricultural yields. As ocean temperatures rise, meltwater from mountain and Antarctic glaciers has caused an increase in sea level, threatening to engulf and destroy productive ields in low-lying areas. While climate change in some regions of the world may reduce yields through looding, other regions are rapidly losing arable land because of severe drought. In the tropics and subtropics, rainfall levels are dropping, and droughts have increased in duration, decreasing crop yields [2]. In highland regions, frost damage due to increased CO2 concentrations has similarly impacted production. However, in certain regions, agriculture productivity may actually rise. In high latitudes, lengthened growing seasons can augment agricultural productivity. Similarly, at high altitudes, higher temperatures may make more land suitable for farming [1]. Furthermore, increased concentrations of CO2 can make water use and photosynthesis more eicient. he simplest method of adapting to changes in speciic environments is modiication of current farming techniques. In semi-arid regions, increasing rates of desertiication have disrupted local ecosystems. Reduced rainfall, coupled with topsoil erosion due to wind, have reduced agricultural yields in the Middle East and sub-Saharan Africa [3]. A group of leading Israeli scientists has gen4 | 2012-2013 | Volume 2
erated mathematical models to optimize vegetation coverage of sand dunes. Changing surface cover can modify local microclimates by afecting wind speed, surface humidity, and absorbed radiation levels. Techniques aimed at reducing grazing stress can halve the number of mobile dunes, decreasing exposed sand surface area and thereby facilitating local botanic agriculture and increasing local water levels. he study also revealed that, in areas where precipitation is suicient, breaking up moss and bacteria layers on the soil can induce vegetation growth and cancel local desertiication [3]. In temperate environments, heat and frost damage are major concerns. If plants mature at too early a time, they will be susceptible to damage from summer temperature peaks and associated dehydration. Furthermore, plants may yield crops earlier in the year as a result of heat stress. As spring temperatures rise, seedlings begin to emerge prior to the last frost. Increasing frost damage presents a serious challenge to agriculture in same extreme latitudes and higher altitudes in which climate change is expected to increase yields [4]. A method that has been useful in combating both of these issues is genetic engineering. he responses of plants to stress can be strengthened by amplifying the chemical signals between the chloroplasts or mitochondria, the organelles that most rapidly detect stress, and the nucleus. Scientists have discovered epigenetic procedures to artiicially induce early crop yields as a means of adapting to shorter growing seasons. Gene splicing techniques using small fragments of RNA can also be used to inluence lowering time; if lowering time is delayed, then most frost damage may be avoided. he transfer of genes from one species to another, transgenics, proves to be an opportunity to adapt the environmental strengths of some species to the conditions that other environments develop as a result of climate change. Heat, cold, and even salinity resistance can be provided by certain combinations of DNA [4]. A prominent example of a recombinant organism designed to combat frost damage is the frost-resistant strawberry grown throughout North Carolina. By inserting genes from the Winter Flounder, which produces anti-freeze compounds to survive in frigid waters, into the genes of a common strawberry cultivar, a strawberry highly resistant to frost was developed [5]. Over the past several decades, agricultural practices have become increasingly homogenous, while environments have become increasingly fractured and diversiied. As traditional agricultural practices are overturned in favor of new methods and heirloom seeds are discarded in favor of a few high-yield varieties, there is a severe risk of losing
Essay
Street Broad Scientific
biodiversity. his potential loss of biodiversity represents a serious threat to future food security by constricting agriculture to a few popular, widespread species, an especially dangerous issue at a time when environmental stresses are diversifying. Additionally, lost biodiversity can reduce the potential of genetic engineering by reducing the availability of genes for transfer. In response, numerous seed banks exist throughout the world, the most prominent of which is in Svalbard, Norway and contains 775,000 samples from 231 countries stored at -18ºC [6]. Solving the issue of anthropogenic climate change by addressing the root cause – CO2 emissions – has been hindered by challenging economic and political issues outside the scope of science. Despite these challenges, it is possible to face the problems caused by climate change through innovative scientiic solutions. he impacts of climate change are diverse, and range from devastating to beneicial. By addressing these issues within the context of their local environments, scientists can mitigate problems and take advantage of new opportunities created by diferent environmental conditions.
References [1] Kurukulasuriya, P., & Rosenthal, S. (2003). Climate Change and Agriculture.Firsov, A. P., & Dolgov, S. V. (1998). [2] World Meteorological Organization. (n.d.). Climate change and desertiication. [3] Kinast, S., Meron, E., Yizhaq, H., & Ashkenazy, Y. (2012). Biogenic crust dynamics on sand dunes. Biological Physics; Geophysics. [4] Mittler, R., & Blumwald, E. (2010). Genetic engineering for modern agriculture: challenges and perspectives. Annual review of plant biology, 61, 443–62. [5] Agrobacterial Transformation and Transfer of the Antifreeze Protein Gene Of Winter Flounder to the Strawberry. [6] Food, M. of A. and. (2007, April 3). Svalbard Global Seed Vault. regjeringen. no.
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