tailieunhanh - IMPACTS OF WATER POLLUTION ON CROP GROWTH IN TAIWAN

As the ratio of oxygen to fuel (or air to fuel) decreases, the products change from the desired carbon dioxide to the undesired carbon monoxide and then to soot (which is almost pure carbon) or unburned heptane. When an engine is operating on a high value of air/fuel ratio, we say the engine is running lean. Sometimes we may also speak of a lean-burning engine. When the air/fuel ratio is low, we say that the engine is running or burning rich. The carburetor or fuel injector system of an engine can be adjusted, at least to some extent, to change this ratio. It would seem,. | Bot. Bull. Academia Sinica 19 107-124 1978 IMPACTS OF WATER POLLUTION ON CROP GROWTH IN TAIWAN IL Phytotoxic Natures of Six Rivers and Twenty Seven Industrial Waste Waters in Kaohsiung Area TaiwanC1 2 Chang-Hung Chou Yueh-Chin Chiang and Chin-I Kao Institute of Botany Academia Sinica Nankang Taipei Taiwan Republic of China Received April 6 1978 Accepted April 20 1978 Abstract This study was aimed to evaluate the phytotoxic natures of polluted waters coming from six rivers and 27 industrial waste waters in Kaohsiung area Taiwan. Results were shown that among three test plants namely lettuce rice and rye grass lettuce was each time the most sensitive to polluted waters and was sharply different from the other two species rice was the second and rye grass was the least affected. The order of phytotoxicity reflected from the water of six rivers is follows Chien-Cheng-Ho Jen-Ai-Ho Ar-Kong-Ten-Chi Ten-Paw-Chi Hou-Ching-Chi Ning-Yuan-Chun. There was a vast area of agricultural land which borders Hou-Ching-Chi where many crops such as rice cabbage turnip and trapa were severely jeopardized. The grain yield of rice along this river was reduced by at least 40 and the number of tiller panicle and test weight were greatly reduced. The phytotoxicity in the waters of Ar-Kong-Ten-Chi Chien-Cheng-Ho Jen-Ai-Ho and Ten-Paw-Chi was correlated with electrical conductivity furthermore the phytotoxicity of the first three was also correlated with osmotic concentration. Two river waters of Ar-Kong-Ten-Chi and Hou-Ching-Chi showed their phytotoxicity being correlated with NH -N content. The phytotoxicity of 27 industrial waste waters varied with factory thus factories Ta-Nun Chung-Yu-Chu-Yun Chung-Chien and Swan-Lu exhibited inhibition higher than 75 of phytotoxicity in all test species. However the phytotoxicity was poorly correlated with the physicochemical properties as studied and the cause was discussed. Introduction Due to the rapid economic and industrial development in Taiwan in .