Mời bạn cùng đọc và nghe phần 1 của Bài đọc và nghe học thuật về Water and Food Security. Các từ khó, câu hay đã được in đậm.
Bài nghe phần mở đầu:
Anyone who can solve the problems of water will be worthy of two Nobel prizes – one for peace and one for science.
John F. Kennedy, President, United States of America, b.1917–d.1963
One Liter=One Calorie
A Critical Link That Equals Water Scarcity
Frank Rijsberman
Water flows uphill to money.
Marc Reisner ~ American author ~ Cadillac Desert, 1986
To produce a calorie of food, it takes a liter of water or at least several thousands of liters of water for every person every day. The water required to grow the food we eat is some 70 times greater than the water we need to drink, bathe and wash. Over the next 40 years the global demand for food is expected to double, and that implies that the amount of water used to achieve global food security would also have to double.
Water pollution affects food quality and health. The plume of foam in the background occurred when polluted water from India’s Krishna River was used to irrigate crops. The river covers 8 percent of the country. © Sanjini De Silva
Nghe phần 1:
Already today a third of the world population is affected by water scarcity. Climate change is expected to worsen this by increasing the frequency and severity of floods and droughts.
That, in a nutshell, paints the grim reality of water and food security. It has led to predictions that future wars will be fought over water and that water will become the blue oil of the 21st century.
What are the water and food challenges faced by the world? Why are they so poorly understood? How did we end up in such a dire situation? Are there solutions to alleviate the world water crisis? These are the questions this article will address.
Hydrocivilizations
In some parts of the world, such as Western Europe and the U.S. Midwest, it is possible to grow high-yielding crops with the moisture provided by rainfall alone. In many others, however, it is either too dry, such as in the Middle East, North Africa or much of California, or rain falls in just a few big storms every year, such as in monsoon Asia. Civilizations that flourished under these conditions all depended heavily on their ability to manage water for agriculture. Irrigation on the banks of the river Nile was the source of wealth in ancient Egypt. Roman aqueducts and underground water tunnels were widespread masterpieces of engineering, some of which have survived until today. Famous kings and maharajahs in southern India and Sri Lanka are remembered as much or more for their dam-building feats as their prowess on the battlefield. Food security has been closely intertwined with water management for millennia, but the speed at which water resources have been developed in recent history has been unprecedented.
During the 20th century, the world population tripled, but the total amount of water extracted from rivers and groundwater aquifers for human use has increased sixfold. By the middle of the last century the global stock of large dams, defined as dams higher than 15 meters, numbered 9,000, three-quarters of which were located in industrialized nations. Today there are some 49,000 large dams in the world, two-thirds in developing countries, particularly in Asia. At the same time, the development of affordable small diesel and electric water pumps led to a boom in groundwater development. In India alone more than 20 million boreholes were drilled and pumped, primarily for irrigation. At the end of the 20th century, global food production was ample to feed the world population (if only the poor could afford it) and food prices were at historic lows, in no small way thanks to a massive global investment in water resources development for food security, hydropower and flood control.
Nghe phần 2:
The Green Revolution
In the 1960s and 1970s, rapidly increasing populations in the Southern Hemisphere and dramatic famines in the Indian subcontinent and sub-Saharan Africa led to widespread fears that the Earth would not be able to support a then-projected population of 6 billion. The Ford and Rockefeller foundations took the lead in initiating major international efforts to boost global food production. These collectively have become known as the “Green Revolution.” The best-known element of this revolution was the much-improved varieties of food crops such as rice, wheat and maize. This effort also yielded the only Nobel Peace Prize ever awarded an agricultural scientist, Norman Borlaug, in 1970 for his development of “famine-busting” semi-dwarf, high-yield, disease-resistant wheat varieties.
This boost in agricultural production required fertilizers and irrigation. The assumption was that making water available cheaply to farmers was part of the core infrastructure, along with roads for example, necessary to boost development and achieve food security. Supported by the World Bank and many bilateral donors such as the United States Agency for International Development, governments throughout Asia and to some extent Africa followed in the footsteps of the massive dam and irrigation canal-building programs in places like the western U.S. and Australia’s Murray-Darling basin. Farmers invested simultaneously in wells and pumps for groundwater development. By the start of the 21st century, 17 percent of agricultural land was irrigated and it produced some 40 percent of the world’s food. Countries such as Thailand, India, Vietnam and Mexico became food exporters, despite their population increases.
Còn tiếp…
Source: USD English State.
Bạn có thể tham khảo cách làm chủ 7000 từ tiếng Anh quan trọng nhất và lộ trình tự học IELTS 7.5.
