Despite years and years of study, I realized I am as ignorant about nature as a seven year old. Years spent memorizing mathematical precision and the science of the heavens, and yet I know very little about what causes a flood. Why they never taught me about nature’s wondrous cycles and interconnection, I still do not know. Thirty years and a post graduate degree, and finally, I learned what it takes for a city to be submerged in water and mud.
Picture this image: When it rains, the water that pours is drank by the soil, trees and plants. The excess water, called a runoff, runs away to water channels like rivers and streams. A flood occurs when two things happen: (1) our soil, trees, and plants cannot drink all the water; (2) and this excess water that runs off, cannot be carried by our water channels (or in modern times, also held by our water reservoirs.) The water then runs to our lands.
The Great Flood in Metro Manila was thus the result of intense rains that poured a huge chunk of water, which (1) cannot be drank in one big gulp by our teeny weeny trees, puny little plants, and inexistent soil; and (2) the excess water had no river or stream to carry them. In fact, our rivers and coasts had overflowed, and our dams had to run off its excess water too.
I wish I could keep writing about the city’s lack of trees and plants, but this is our Flower Farm blog and so I will write about an equal champion against floods, the soil. Throughout history, we have created floods as a direct result of soil erosion. Soil erosion is a natural occurrence. As long as there are rains and winds, the soil will be carried off in pieces. But, nature is wise and never wasteful. What the soil losses through erosion is always balanced by new soil. If you look at virgin land masses, you will always see how nature forms a mantle of vegetation to protect the soil. When rain falls on this protective mantle of grass or fallen leaves, some of the water’s moisture can still evaporate before it reaches the ground. Nature also has a troop of trees, grasses and roots that help to hold the soil in place even amidst the slaughter of rain and wind.
How do we learn from nature’s subtle but nurturing ways? I see now that when we engage in commercial farming without regard to the soil’s natural processes, we partially or wholly destroy nature’s protective canopy. Intense cultivation digs up vegetative covers of the soil, removing the soil’s umbrella from too much rain. When we dig up trees, grasses and roots that surround our farm, to give way to our crops, we shoo away nature’s defenses. Our farm has a lot to learn but we have started some methods that simulate the marvelous processes of nature. One way to hold back flood is to restore the vegetation in our soil. We do this through crop rotation, cover cropping, and using bulky organic manure. We cover our crop beds with the leaves of legumes. To prevent the water from running off, we plant nitrogen-fixing legumes and calla lilies beside the water canals in between our greenhouses. These legumes and lilies act like buffer zones to slow down run off and trap the soil, so that these are not washed out by the rain. Our canals are dug at critical places on a slope so excess water falls into the canals, and through the natural contours of the land, the excess water irrigates the plants in the beds. These are some of the methods we use and everyday nature readily gives us a clue. I admit I am quite a beginner in understanding the mind-boggling ways of nature. But I am a willing learner. Because who else would teach me about something so simple, and yet so grand?