Bulletin

wall bulletin
South AmericaCrop and environmental conditions in major production zones

Authors: 超级管理员 | Edit: xingqiang

Uncultivated arable land was very low this season, further decreasing over the already very low values of the recent past. This is in contrast to the potential biomass ratio which decreased as well, indicating a some what reduced efficiency of farming systems in the MPZ. Altogether, however,trends are positive, as illustrated by the significantly increasing trend of cropping intensity, up 8.3 percent over the recent medium term, most of the increase being achieved over the last five years.

Table 2.3 South America MPZ: Croppingintensity, uncultivated arable land, and potential biomass ratio


2013 value

11-year average (2002-12)

5-year average (2008-12)

2002-13 normalized trend

Coefficient of correlation

Significance level of trend

Difference between 2013 and 11-year average

Difference between 2013 and 5-year average

Cropping intensity (%)

144

136

137

6.10

0.583

*

8.3

6.9

Uncultivated arable land (%)

0.14

0.17

0.25

6.49

0.182


-0.02

-0.11

Potential biomass ratio

0.865

0.880

0.885

0.000

0.135

 

-0.016

-0.021

Note: The normalized trend is the 2002-2013 trend normalized by dividing it by the eleven-year average. Significance level of the trend is *for p<=0.05 and ** for p<=0.01.

Few significant long-term environmental trends affect th eregion, with the exception of PAR trends which parallel those in the northern part of the continent: PAR increased significantly, by about 5 percent since2001. Other variations worth mentioning include temperature and rainfall, which both increased over last year.

Figure 2.4 Environmental and crop productionindices for the South America MPZ