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1、<p>  1860單詞,2628漢字</p><p>  出處:Wijeratne M A. Vulnerability of Sri Lanka tea production to global climate change[J]. Water Air & Soil Pollution, 1996, 92(1-2):87-94.</p><p><b>  

2、原文 </b></p><p>  VULNERABILITY OF SRI LANKA TEA PRODUCTION TO GLOBAL CLIMATE CHANGE</p><p>  M.A. WIJERATNE</p><p>  Introduction </p><p>  Although industrial ex

3、ports such as textiles and garments bring in a higher percentage of foreign exchange, agriculture is the highest net foreign exchange earner in Sri Lanka. Of the agricultural exports, tea alone contributes about 15-25% o

4、f the total exchange earnings and, hence, plays a key role in the Sri Lankan economy. About 30% of the employees of the public sector government and semi government are manual workers on estates, and the majority of thes

5、e are employed on tea plantations. Mor</p><p>  In spite of the expansion of the small holdings sector, in Sri Lanka, the total area of tea plantations has decreased since the 1930s, i.e., from about 0.44 to

6、 0.23 x 10 s ha. The decline in the estate sector tea lands began early in the 1960s, because of low productivity brought about by soil and bush debilitation. Many of the mid country 600-1,200 m elevation tea plantations

7、 have now become marginal, warranting crop diversification. Adversities of weather and poor management practices have bee</p><p>  Being a rainfed plantation crop in Sri Lanka, tea depends greatly on weather

8、 for optimal growth. Therefore, changes in weather conditions would undoubtedly affect tea production. The relationship between tea yield and weather has been discussed by many researchers e.g., Devanathan, 1975; Kandiah

9、 and Thevadasan, 1980; Carr and Stephens, 1992. The findings of this study differ from those of the Sri Lanka country report ADB, 1994. This could be due to the different models used to predict tea yield.</p><

10、p>  Droughts inflict irreparable losses to the tea industry and hence to the economy of Sri Lanka. The consequences of the droughts in 1983 and 1992 are good examples Central Bank, 1983; 1992. The decline in productio

11、n due to drought in early 1983 was about 4% over the previous year, and the drought in 1992 reduced tea production by about 26% compared to that of 1991. It also increased the costs of production by 19%, depriving the co

12、untry of about 3 billion rupees US$70 million of foreign exchange. </p><p>  Heavy rainfall also causes considerable damage to tea plantations through soil erosion, poor growth due to lack of sun, and increa

13、ses in disease incidence. Poorly covered old seedling tea fields, pruned tea fields, and young tea fields during the first two years are more vulnerable to soil erosion due to inadequate ground cover. It has been estimat

14、ed that more than 30 cm of top soil has already been lost from Sri Lanka's tea plantations, especially in the uplands Krishnaraj ah, 1985. Landslides </p><p>  Climate Change and Methods </p><

15、p>  According to climate change scenarios, the increases in global atmospheric CO 2 concentrations and temperatures by 2100 could be in the range of 600-700 ppm and 1.0-3.5 °C, respectively, compared to 1990, dep

16、ending on different scenarios of variations in greenhouse gas emissions CO2, CH4, N20 and oceanic changes Houghton et al., 1996The consequences of climate change will differ from one country to another. In the recently p

17、ublished Sri Lanka country report ADB, 1994, it was shown that Sri Lanka</p><p>  In many other countries, vulnerability assessments on different economically and socially important areas are being conducted

18、 to inform policy makers about suitable adaptation measures that could be implemented. Hence, it has become a current need to address the possible impacts of global climate change on the tea industry in Sri Lanka .</p

19、><p>  In this study, the effects of environmental factors on growth and yield of tea were studied using data on annual variation of climatic factors and yield parameters of tea. The relationship between the cl

20、imatic factors and tea yield was analyzed using linear regression analysis.</p><p>  Results and Discussion </p><p>  As described previously, since there is no irrigation, tea yield is greatly

21、influenced by weather Tea grows well under air temperatures in the range of 18-25 °C Carl 1972; Watson, 1986. A well-distributed rainfall of about 1,300-1,400 mm per year is generally considered adequate for the gro

22、wth of tea in Sri Lanka. It is also reported that an annual rainfall of about 2,500-3,000 mm is optimum for tea cultivation Fuch, 1989; Watson, 1986. There is a wide variation in temperature and rainfall in th</p>

23、<p>  Although the relationship between weather and tea yield has shown that increases in rainfall and temperature increase tea yield Devanathan, 1975; Squire, 1990, recent observations have shown that at higher te

24、mperature regimes 25-26 ° C, the yield components of tea shoot population density, shoot weight, and shoot extension rate tend to decrease with increasing temperatures: </p><p>  SW=0.647 (4-0.059)- 0.0

25、17 (4-0.002 T )</p><p>  R2 =40%, p 0.001 , </p><p><b>  and </b></p><p>  SER=225 ±38- 6.62( ±1.37) T </p><p>  R2=29%, p 0.001 , </p><

26、;p>  where SW, SER, and T are the shoot dry weight g/shoot, shoot extension rate mm/week, and temperature °C, respectively. Low R 2 values were obtained because this experiment was conducted under field condition

27、s where none of the environmental factors were controlled Figure 2 shows the relationship between tea shoot population density and temperature for TRI 2025 and TRI 2023, two common tea clones cultivars in Sri Lanka.</

28、p><p>  Experiments under controlled environments have shown that shoot extension rate increases with increasing temperatures up to 22°C, and further increases in temperature up to 34°C result in a de

29、cline in the extension rate Figure 3; the dashed lines below 15 °C in the figure are extrapolations of the linear relationship to obtain the base temperature above which tea grows .</p><p>  The adverse

30、 effects of climate change are expected to be greater in the low country tea growing regions 600 m above mean sea level where the mean air temperatures are usually higher than 25°C and drought damages are greater. H

31、owever, this is the region where the majority of tea production enters the market Figure 4. Further, most of the small holdings are concentrated in the low country districts </p><p>  The effects of drought

32、on tea plantations are well known Wijeratne and Ekanayake, 1990; Navaratne, 1992; Yatawatte, 1992. Increases in temperature, soil moisture deficit, and vapor pressure deficit create a plant water deficit, which leads to

33、growth retardation. Experimental results in the low country have shown that clonal tea yields could be adversely affected at temperatures 26°C, soil moisture deficits 30-50 mm, and saturation vapor pressure deficits

34、 1.2 kPa Wijeratne, 1994. Given these resu</p><p>  Extreme rainfall events within a short period of time also cause considerable damage through erosion. Loss of fertility, reduction in water holding capacit

35、y because of an increase in graveliness, exposure of hard pans, exposure of root systems, and reduction in microbial activities due to loss of organic matter are some of the negative consequences of soil erosion, adverse

36、ly affecting the growth and yield of tea. With the loss of top soil, cultivable lands may become barren or unproductive and c</p><p>  When these facts are considered, it is clear that the predicted climate

37、change in Sri Lanka, i.e., recurrent warm seasons, droughts, and heavy rains with erratic distribution, will undoubtedly affect the tea industry. Tea needs an even distribution of rainfall to ensure continuous production

38、. Although increased atmospheric CO 2 levels can enhance photosynthesis, this beneficial effect cannot be expected to offset the negative impacts expected because of limitations such as high temperatures and </p>

39、<p>  Currently, more than 50% of Sri Lanka's tea fields are seedling fields with poor ground cover. Although these seedlings are generally more adaptable to environmental stress, their ability to withstand dry

40、weather is being degraded by poor soil and poor management. Most of these fields are planted along the slope but not on contours and hence are also vulnerable to soil erosion. Recent observations have shown that even see

41、dling tea fields are subject to drought damage due to poor shade and poor s</p><p>  Shade is an essential requirement in tea plantations: shade trees reduce temperature, conserve soil, and increase relative

42、 humidity. After the abrupt removal of shade trees in the early 1960s shade was removed with the hope that an increase in light intensity would enhance the assimilation of tea, shade management in Sri Lanka's tea pla

43、ntations was very poor. Under such conditions, vulnerability of the tea industry to global warming and soil erosion will be much greater As a result of the poor m</p><p><b>  譯文</b></p>&l

44、t;p>  氣候改變對斯里蘭卡茶產(chǎn)業(yè)的影響</p><p>  作者: M.A. WIJERATNE</p><p><b>  簡介 </b></p><p>  雖然紡織品和服裝類工業(yè)的出口帶來了很高比例的外匯,但是,在斯里蘭卡,農(nóng)業(yè)出口是最高的凈外匯收入來源。而在農(nóng)業(yè)出口中,單單茶葉就占了整個外匯收入大約15 至25%的比例。因而在

45、斯里蘭卡經(jīng)濟中起了決定性的作用。在公共部門(政府和半政府)中,大約30%的雇員是工廠的手工工人,其中,大部分在茶葉種植廠里就職。而且, 大約 239000 茶葉小廠家提供了大量的國內(nèi)就業(yè)機會。相應(yīng)地,多于700000 的工人和他們的家庭都依賴于茶產(chǎn)業(yè)。這些數(shù)據(jù)充分顯示了茶產(chǎn)業(yè)在斯里蘭卡社會和經(jīng)濟中的重要性。 </p><p>  自從20世紀30年代以來,盡管一些小廠家得到了擴張,但是在斯里蘭卡,茶業(yè)種植的總體區(qū)

46、域是呈現(xiàn)縮減趨勢的,比如說,從0.44 *10 到0.25 * 10 ()。由于土地和灌木叢無力而導(dǎo)致的生產(chǎn)力低下,茶產(chǎn)業(yè)部門的土地占有率從20世紀60年代開始減少。很多國家中部的 (600到1200 米的高地)茶葉種植區(qū)已經(jīng)趨于邊際,作物出現(xiàn)多樣化。惡劣的氣候和管理實踐水平的低下是造成這種情況的主要原因。20世紀60年代初,在陰影區(qū)消除之后,茶葉種植區(qū)的氣候變化已經(jīng)影響了茶樹的生產(chǎn)力 (Fuch, 1989)。20世紀70年代,茶生產(chǎn)

47、的國有化所產(chǎn)生的一些副作用,比如對農(nóng)業(yè)生產(chǎn)實踐的忽視,導(dǎo)致了私有部門生產(chǎn)力的降低 Fuch, 1989。作為一個斯里蘭卡雨養(yǎng)地生產(chǎn)作物,茶產(chǎn)業(yè)的最優(yōu)生長很大程度上依賴于氣候。氣候和茶產(chǎn)量的關(guān)系已經(jīng)被很多研究者討論過。比如Devanathan, 1975; Kandiah 和 Thevadasan, 1980; Carr 和 Stephens, 1992。在他的報告中關(guān)于水資源,空氣和土壤污染的發(fā)現(xiàn)和斯里蘭卡的國家報告是不一樣的ADB,

48、1994。這種情況可以歸結(jié)于在預(yù)測茶</p><p>  大量的降雨也通過土壤流失,缺少陽光而導(dǎo)致低生產(chǎn),疾病發(fā)生率的提高,給茶生產(chǎn)帶來了巨大的損壞。由于土壤覆蓋面的不足,在頭兩年里,一些土壤表皮很薄弱的茶地,修理過得茶地,以及一些新的茶地很容易受土壤流失的影響。在斯里蘭卡,經(jīng)估計,大于30厘米的茶種植地表皮已經(jīng)流失,尤其是在高地Krishnaraj ah, 1985。山崩滑坡也對種植有負面的影響,同時也會危害在

49、斜坡面工作的工人的生命。 </p><p><b>  氣候變化和方法 </b></p><p>  根據(jù)氣候變化記錄,到2100年,全球大氣中二氧化碳的集中度和氣溫的上升將分別在600到700ppm,以及1.0到3.5攝氏度的范圍之間。 環(huán)境因素在茶產(chǎn)量和生長系數(shù)上的影響力在這個研究中做了分析,主要采用氣候因素和茶葉的產(chǎn)量系數(shù)的年變化數(shù)據(jù)。氣候因素和茶葉的產(chǎn)量系數(shù)之

50、間的關(guān)系通過線性回歸分析。 </p><p><b>  結(jié)論和討論 </b></p><p>  在先前描述過,由于沒有灌溉,茶葉產(chǎn)量在很大程度上受氣候影響。在18度到25度的溫度范圍內(nèi),茶葉生長良好Carl, 1972; Watson, 1986。良好的雨水分布,每年大約在1300到1400毫米左右,是足夠供斯里蘭卡的茶葉生長。有報道指出,2500到3000毫米左

51、右的年雨水量能夠促成茶葉種植的最優(yōu)(Fuch,1989;Watson, 1986)。在斯里蘭卡,不同地區(qū)的氣溫和降雨量有很大的差異。 </p><p>  雖然氣溫和茶產(chǎn)量之間的關(guān)系顯示,降雨量和氣溫的增加會導(dǎo)致茶產(chǎn)量的增加Devanathan, 1975; Squire, 1990, 但是最近發(fā)現(xiàn)顯示,越高的氣溫物理環(huán)境大于25到26攝氏度,茶葉的產(chǎn)量成分 (嫩枝的密度,重量和稀釋率)將會隨著氣溫的升高而趨于減

52、少。</p><p>  SW=0.647 (4-0.059)- 0.017 (4-0.002 T )</p><p>  R2 =40%, p 0.001 ,</p><p>  SER=225 ±38- 6.62( ±1.37) T</p><p>  R2=29%, p 0.001 ,</p><

53、p>  其中,SW, SER 和 T 分別代表干嫩芽的重量 (克),嫩芽的稀釋率(毫米/周) 以及溫度(攝氏度)。結(jié)果得到較低的R2 是因為該實驗是在沒有任何一個環(huán)境因素受控制的情況下進行的。 </p><p>  在茶葉低生長區(qū)域海拔600米,平均空氣溫度一般高于25攝氏度,同時大旱的破壞力也更大,這些區(qū)域里氣候變化的負面影響將比預(yù)期更大。但是,這些區(qū)域中的大部分茶葉將進入市場。而且, 在農(nóng)村區(qū)域的低地,

54、大部分小工廠集中起來。 </p><p>  大旱對茶葉種植的影響是眾所周知的(Wijeratne, Ekanayake,1990; Navaratne, 1992; Yatawatte, 1992)。氣溫的變化,土壤水分流失以及水蒸汽壓力的流失產(chǎn)生了大量的水分流失,從而導(dǎo)致了生長延遲。低地的實驗結(jié)果顯示,在溫度大于26攝氏度,土壤水分流失大于30到50毫米,飽和水汽壓力流失大于1.2kPA的情況下,無性繁殖的茶

55、葉產(chǎn)量是會受到負影響的Wijeratne, 1994。給出的這些結(jié)論可以推測出,斯里蘭卡的預(yù)期氣候變化,比如說氣溫升高,氣候變更加干燥 (ADB,1994),都將不利于茶葉的生產(chǎn)。 </p><p>  在一個短時間里,極端的降雨事件也會因水土流失而導(dǎo)致不可計量的破壞。肥沃力的破壞,雨水儲存能力的下降,硬土層的暴露,根部的暴露以及微生物活動的減少,都是一些水土流失的負面結(jié)果,都不利于茶葉的生長和產(chǎn)量。隨著土壤表皮

56、的流失,可種植的土壤會變成禿地或者是無生產(chǎn)力的土地,這些土地既不能用于茶葉再種植,也不能用于其它農(nóng)業(yè)用途。并且,這些土地的修復(fù)需要很長的時間,極有可能是不經(jīng)濟的。此外,由于陽光的不足和疾病發(fā)生率的增加,比如說茶樹也會因為大量的降雨減少生長。很明顯,在斯里蘭卡,預(yù)期的氣候變化,比如說周期性的暖季,干旱和不穩(wěn)定分布的強降雨,毫無疑問得都會影響茶產(chǎn)業(yè)。茶葉需要均勻的降雨分布來保證持續(xù)的生產(chǎn)力。雖然大氣二氧化碳水平的增加會加強光合作用,但是由于

57、比如高溫和劣質(zhì)的土壤條件,這個有利影響不能夠用來彌補預(yù)期的不利影響。 </p><p>  現(xiàn)在,大于50%的斯里蘭卡茶地是土壤表層覆蓋薄弱的播種地。雖然這些種子會逐步地適應(yīng)環(huán)境壓力,但是由于劣質(zhì)土壤和不熟練的管理,他們承受干燥氣候的能力正在退化。大部分這樣的土地都沿著斜坡種植(但不是在等高線上),因此,也很容易受水土流失的影響。 </p><p>  最近的研究顯示,即使是播種茶山地,也

58、會由于不優(yōu)的遮陽條件和不良的土質(zhì)而免不了干旱的影響(Yatawatte,1992)。因此,播種茶山地也將因為氣候變化而受到不可估計的危害。遮陽是茶葉種植的很關(guān)鍵的一個要求,遮陽樹能夠減少氣溫,保持土壤,以及增加相對潮濕度。20世紀60年代初,在失去了遮陽樹之后(隨著遮陽樹的失去,用于增強茶葉吸收的光線密集度也會增加),斯里蘭卡的茶葉種植,對陰涼的管理是很欠缺的。在這種情況下,茶產(chǎn)業(yè)更容易受全球氣溫變暖和水土流失的影響。 </p&g

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