水土保持草類對土壤含水量、光度及温度之反應

Responses of Soil-conserving Grasses to Soil Moisture, Light Intensity and Temperatures

10.29417/JCSWC.198811_19(2).0001

林信輝(Shin-Hwei Lin)

水土保持草類 ； 環境因子 ； 生理反應 ； Soil conserving grasses ； environmental factors ； physiological responses

中華水土保持學報

19卷2期（1988 / 11 / 01）

1 - 13

繁體中文

本試驗選取八種水土保持草類，在控制環境下測定各草類之生長及有關生理現象對土壤水分、光度及溫度之反應性差異，藉以探討各草類之耐旱性，低光利用效率及對高低溫之適應性等，以供植生草種選擇與推廣之參考。茲將所得結果摘述如下：1.就相對生長率而言，八種草類在中等土壤含水量之情況下，百慕達草，兩耳草及假儉草之相對生長率較高，顯示其初期生長較快。比較乾旱土壤水分處理區（1）與其他處理區間之相對生長率，百慕達草、假儉草及百喜草A33處理間差異較小，表示其受乾旱生長之影響較小，但百喜草A44、地毯草之生長率受乾旱之影響較大。2.地毯草與兩耳草在低光下之相對光合成率較高，顯示較適於低光下生長。百慕達草之低光利用效率最低，其他五種草類則介於其中。3.八種草類在低溫（10℃）時葉片之相對光合成率（對葉溫30℃時之淨光合成率比値），由最高至最低依次爲假儉草與百喜草A44，奥古斯丁草，兩耳草，百慕達草與類地毯草，百喜草A33，地毯草。在高溫（40℃）時之相對光合成率依次爲兩耳草，百喜草A44，百喜草A33與百慕達草，地毯草，奥古斯丁草，類地毯草，假儉草。顯示假儉草與百喜草A44較適於低溫下生長，兩耳草，百喜草與百慕達草較適於高溫下生長。本文僅探討短期之生理反應，實際田間長期乾旱，遮蔭或高，低溫情況對光合成產物分配之影響及對病害之誘發等尙待瞭解。故若能配合野外之試驗結果，並提供合理之解釋及解說，則本研究將更具價值。

Growth rate and physiological phenomena of eight soil conserving grasses of Taiwan were measured under different soil moisture, light intensity and temperature. Drought tolerance, shading and temperature adaptations of those grasses were studied. Results obtained are summarized as follows: 1. Under medium soil water content (treatment lI-V), Burmuda grass, buffalo grass and centipede grass had higher relative growth rate (RGR) and showed higher rate in the initial growth stage than the other species. Comparing the RGR under the lowest soil moisture treatment (I), Bermuda grass, centipede grass and Bahia grass A44 were less different with other higher soil moisture treatment. That indicated they were less influenced by serious drought, but Bahia grass and carpet grass (Axonopus compressus) were very sensitive to drought. 2. Carpet grass (Axonopus compressue) and buffalo grass had high relative photosynthetic rate under low light intensity and they were more suitable to grow in shading. Bermuda grass and centipede grass had the lowest efficiency to use weak light. 3. The sequence of relative photosynthetic rates at low temperature (10°C) from the highest to the lowest was centipede grass, Bahia grass A44, St. Augustine grass, buffalo grass; Bermuda grass and carpet grass (Axonopus affinis), Bahia grass A33, carpet grass (Axonopus compressus). The sequence of relative photosynthetic rates at high temperature (40°C) was Buffalo grass, Bahia grass A44; Bahia grass A33 and Bermuda grass, carpet grass (Axonopus affinis), centipede grass. That indicated centipede grass and Bahia grass A44 were more adaptable at low temperature and buffalo grass, Bahia grass and Bermuda Grass were more suitable at high temperature. Only short term plant physiological responses were mentioned in this paper. The actual field status of drought, shading and temperature variation, such as the effects of long term environmental stresses on photosynthetic product allocation and on pest (disease) infection has to studied further.