ارزیابی اقتصادی از تغییرات تکنولوژیکی و تخریب زمین در بخش کشاورزی: ​​برنامه ای به بخش چای سری لانکا

Productivity change is an important potential aspect of technological change, so that productivity measurement plays a crucial role in assessing the effects of technological change in agriculture. This study contributes to an understanding of total factor productivity change by assessing the extent and nature of such change for the Sri Lankan tea industry over the period 1960–1995. The total factor productivity measures are then used to define a conceptually sound measure of the production cost of land degradation, providing insight into the scarcity of soil in the tea sector. Based on the theoretical relationship of the impact of technological progress and land degradation on tea production, a regression model is fitted to decompose the total factor productivity variable. Technological change, when the study period as a whole is considered, produced cost savings, rather than output increases. Tea output levels have been maintained, despite significant decreases in total inputs. On the basis of available data and the chosen model, it could be concluded that the positive impact of technological progress has outweighed the negative effect of land degradation in Sri Lanka's tea sector, over the study period. The study highlights the systems aspect of analysis into the productivity and land degradation issues in agriculture.

Technological change, also known as technical change, refers to changes in techniques of a production process that come about both from research and development and from learning by doing. These changes in the production process can be realised in various ways at the business level: through improved methods of utilising existing resources such that a higher output rate per unit of input is obtained, often referred to as disembodied technological change; through changes in input quality, referred to as embodied technological change; or through the introduction of new processes and new inputs. Productivity change is an important aspect of technological change, so that productivity measurement plays a crucial role in assessing the effects of technological change in agriculture. Total factor productivity (TFP), the productivity of all purchased inputs, is the broadest measure of productivity, and is clearly the most useful approach to productivity measurement when the objective is to understand the effects of technological change (Norsworthy and Jang, 1992).

Total factor productivity in the Sri Lankan tea sector increased at an estimated annual rate of 1.82% between 1960/1961 and 1994/1995. This resulted from an estimated annual rate of increase of 0.01% in total outputs and a considerably larger rate of 1.81% annual decrease in total inputs. Hence the reason for TFP growth was largely due to decreased use of inputs rather than increased output. Technological change during the study period as a whole seems to have been directed more towards producing cost savings than to generating output increases. Land and capital inputs showed significant negative growth trends confirming lack of sufficient long-term investments in the tea sector. The increasing levels of input use in the early years with a subsequent downward trend and the seasonal conditions affecting output have been important causes of short-run fluctuations in productivity around the underlying trend productivity increase. Total output quantity increased till 1965 and then trended downwards till the early 1980s; thereafter significantly increasing again.