Seite - (000158) - in Evaluating Climate Change Action for Sustainable Development

market – such as soybean – travel time is likely to have a negative effect on the probability that theyareproducedandon theamountof landareadevoted to them. Totheextent thatuplandriceandpaddyricearegrownforsubsistence, thiseffect is expected tobe insignificant.Moreover, if the only reason that the crop is grown is that it is a substitute for a staple that can be bought in themarket, then the travel time coefficient is likely to be positive. The variable in the dataset measures the ‘average time taken one way, in minutes, to reach the market, using the most popularmodeof transport.’ It thus takes into considerationmodeof transportation and roadquality.21 Proportion of Adult Population The proportion of adults in the village is expected to positively affect land brought under cultivation and the intensitywith which it is cultivated. Adult labor is required to grow crops on virgin land that requires preparation.22,23 The presence of more adults is likely to increase the amount of land cultivated and ameliorate labor scarcity. In this study, proportion of adult population is used as a proxy for available labor in the village and for the opportunity cost of labor. ProductivityofLand Thereare twovariables that areusedasaproxy tomeasure land productivity. These are water availability and a dummy for acidic soil.24 (Please see below.) Additionally I also use a time invariant binary variable to indicate whether the village grew high yielding varieties (HYV) of rice at any time during the study period. (SoHYV rice dummy¼1 if the village ever grew HYVriceduring thestudyperiod,and¼0otherwise). Iexpect thisvariable tohave two impacts on productivity. The first is on paddy rice area: HYV rice is more productive thannon-HYVrice. I expect it tohaveapositiveeffectonareadevoted topaddyrice.Theothereffect thisvariable is likely tobeaproxyfor is thepresence (or absence) of ‘attention’ from local authorities. To the extent that growingHYV rice requires additional knowledge and training provided byfield officers and that 21See for exampleDawson andBarwell (1993). 22Itwouldbeuseful to gauge thedifferent impacts of adultmales and adult females. 23SeeGodoyet al. (1997) for a similar argument. 24Another possible variable is yield per acre but there are problemswithmeasuring the variable since it is measured only when crop data are available. It is also potentially endogenous. For example foruplandriceyield/hectare is availableonly for541observations, or248villages forat leastonepoint in time.For thesubsetofvariables forwhichdataareavailable:For soybean, there is a positive time trendwhen the log of productivity is regressed on year, while controlling for other variables (~3%). when we regress this variable for soybean on time dummies, the time dummiesare insignificant (and indeed in thefirst twoyears,negative, compared to1986.Theyare positive in the next 2 years but insignificant. Only in 1996 is the time dummy significant and positive –when an average increase of almost 30%occurs). Similarly for upland rice, the time trend is not significant or large (although it is positive). This indicates that therewere not very many productivity increases among farmers located in Forest Reserve villages of ChiangMai, during 1986–1996, although somemayhave taken place in the last year of the study period, for soybean.Witnessing an increase in area despite there being an increase in productivity, further strengthenmy results. 142 J. Puri