hindsight knowledge of the fact that parts of theu.s.crop suffered dry conditions early in the season, pushing prices even higher.
Assessing the size of the Brazilian soybean crop is made especially difficult by the fact that there are many estimates at a point in time, including estimates from two different Brazilian government sources. During the critical month of March 2005, when prices were rapidly escalating, estimates ranged from 56 to 61 mil- lion tons, with Brazilian Government estimates of the crop ranging from 57 to 61 million tons. Timely clarification of the specific size of the crop was critical in the weeks approaching the U.S. planting season. Meteorological data and analysis pro- vided critical insight into the unfolding situation in Brazil and enabled timely dis- semination of information to the global marketplace.
In March 2006, yet another year in which drought was affecting the Brazilian soybean crop, the Brazilian Government released a yield estimate of 2.4 t hal for the state of Mato Grosso do Sui, down from its previous estimate of2.7 t hal. USDA was at the time estimating the yield at 2.65 tons per hectare. Our issue was wheth- er we should lower our production estimate for Brazil in light of the new Brazilian yield estimate.
A significant problem in evaluating this new estimate was the lack of meteoro- logical data for the state. WMO stations and general soybean producmg areas for Mato Grosso do Sui are depicted in Figure 9.10.
• WMO Stations
Mato Grosso do Sui
*Soybean production IntensityD _
Low High
• Average from2002to2004 (Source: IBGEBrazil) Fig.9.10 WMO stations and soybean producing areas for Mato Grosso do SuI.
An accurate analysis would require a combination of all of the available tools.
Temperature and cumulative precipitation charts with comparisons to normal values and to 2002 (selected as an analog year) revealed nothing to suggest a sig- nificant yield reduction was appropriate at that stage of the crop cycle. The soil moisture profile depicted in Figure 9.11 shows a drying period from mid-January through early February, but recharge returned values to historic norms by early March. Again, no clear indication was presented to reduce yield. However, with the limited availability ofWMO station data, more analysis was necessary to con- firm the estimate. Weekly CMORPH data were analyzed, typified by Figure 9.11 for February 19-25:
With CMORPH data and analysis supporting conclusions from other weather indications, a case was developing to hold off on reducing the Brazilian crop due to yield deterioration in Mato Grosso do SuI.
Further analysis of the situation was conducted through application of satellite imagery crop masking techniques to more clearly identify soybean producing ar- eas and comparative NDVI analysis of the region. These techniques are depicted in Figure 9.12.
With major soybean areas outlined in the south-central and northern regions, it is apparent that 2006 was faring better than 2002 in some cases, and in the areas with lower NDVI scores, soybean production was not highly concentrated.
CMORPHEstimated PCP Feb19-25, 2006
~ Lower(1ã10mm)
11
. . Higher(>200mm)
Fig.9.11 CMORPH estimated PCP, February 19-25, 2006.
Chapter9: Methods of Evaluating Agrometeorologi(al Risks 139 From the combination of analysis of data for Mato Grosso do Sui for early 2006, it was concluded to leave the yield unchanged at 2.65 t ha' for that month. How- ever, the analysis continued throughout the crop cycle, leaving open the possibility that the crop estimate could be adjusted in later months.
9.7
Conclusions
Risk and uncertainty affects every aspect of the agricultural commodity market- ing system - from producer to final consumer. Weather-related yield and price risk translate into income risk in agricultural markets around the world. Ac- curate, timely, consistent, objective, and widely available information including analysis of the impacts of weather on crop production is critical for economic en- terprises to make optimal business decisions. This paper reviews methods used at USDA to assess impacts of weather-related risk and uncertainty on global crop production as a first step toward estimating global supply and demand for com- modities. More timely and accurate estimates result when multiple analytical techniques are employed to evaluate the impact of seasonal weather conditions on crops.
MODIS 250m - 8daycomposite
Average (Jan 9 - Feb 2)NOV! Difference for 2002 - 2006
o 190 380 760 Km
- - --- USDA Agricultural Research Service
- - Remote Sensing Laboratory
Legend
_: 2006 better than 2002
- -
- --l1li
..;TIm
~-lii!i
:.:il<!l
'~4~mil 2006 same as 2002
- -
lIIIIII
-
liil!I :;'2l
-
IIIlIIl
-- --
- - =2006 worse than 2002 :-J Soybean Areas
Fig.9.12 NDVIdifference for2002VS. 2006.
References
USDA (2006) Risk Management, USDA 2007 Farm Bill Theme Papers, May 2006. www.usda.
gov/documents/Farmbill07riskmgmtrev.doc
CHAPTER 10
Weather and climate and optimization
offarm technologies at different input levels
Josef Eitzinger, Angel Utset, Miroslav Trnka, Zdenek Zalud, Mikhail Nikolaev, Igor Uskov
10.1
Introduction
Weather and climatic conditions are the most important production factors for ag- riculture. Farmers within any agroecosystem therefore try to adapt to these condi- tions as much as possible (Adger et al. 2005; Smit and Yunlong 1996). Farm tech- nologies playa major role in this adaptation process in both the short and the long term. Farm technologies are optimized for different purposes such as maximizing food production or profit. There is an urgent need, however, for such aims to be directed to permit sustainability of food production at the local level, which can be based only on stable agroecosystems (Fig.lO.l). This has to be the basic strategy
... by increasingtheefficient use of inputs
(fertilizer, machinery, ...) andnatural resources
(soU, water, crop, microclimate)
Fig. 10.1. The short and long term impact factors on farm management and its relation to re- source management and sustainability of agricultural production.
for the long term as important resources for agricultural production such as water, land and soil resources are highly limited in our world. Moreover, these resources are also endangered in many regions by desertification and climate change.
New farm technologies and those that have been established for many genera- tions - indigenous technologies - offer many opportunities to react or adapt to the given climatic and weather conditions. Because of climate variability and change, the optimization of farm technologies becomes even more important for the pro- ductivity of various agricultural production systems at different input levels (Siva- kumar et al. 2005). Available farm technologies are often closely linked to specific management options, which will therefore be considered as well in the following analysis. These options for the various agricultural systems are always embedded within the given socioeconomic, policy and trading framework within and be- tween countries and regions and these can vary widely. This framework is an im- portant consideration when identifying measures to adapt to weather and climate conditions and has a strong influence on the adequacy of measures for adapting farm technologies (Chiotti and Johnston 1995). This background and impact are not considered in detail in our analysis but should be kept in mind when applying the general findings and examples to a region with specific agricultural systems and conditions.
Using available farm technologies to ensure sustainable production within giv- en climatic and weather conditions often calls for the proper management of re- sources or conditions for a specific agricultural crop production such as water, soil (including nutrients), crops (including crop management) and microclimate (Igle- sias et al., 1996; Karing et al., 1999; Rounsevell et al., 1999; Salinger et al., 2005).In all agroecosystems since farming began farmers have developed specific strategies, mainly the use of different farm technologies and related management options, to survive in the given environment, but for various reasons not always with sustain- ability in mind.
However, the development or improvement in farm technologies has been re- sponsible for most of the increases in productivity and yields in agricultural pro- duction worldwide. This trend should continue (Rounsevell et al. 2005) and could potentially outrange, for example, any negative effects of climate change impacts on food production in many regions. For a specific agricultural system not only the applicability but also the availability of appropriate technologies for the local farm- ers is therefore crucial for the potential to optimize production or adapt to climatic variability and change conditions.
For example, the proper management of water resources by application of ap- propriate farm technologies plays and will playa major role in both developed and developing countries in regions with limited water resources for agricultural pro- duction. Yield and yield variability can be strongly affected by global warming and changing climatic variability including the direct effect of CO2on water use effi- ciency in agroecosystems (Curry et al. 1990; Downing et al. 2000; Dubrovsky at al.
2000; Erda et al. 2005; Ewert et al. 2002; Isik and Devadoss 2006; Kartschall et al.
1995; Semenov et al. 1993; Semenov and Porter 1995; Wolf et al. 2002). Crop water use and deficit in different climate scenarios and potential adaptation measures, however, depend on crops, soil and climatic conditions and have a mixed impact
Chapter 10: Weather and climate and optimization offarm technologies atdifferent input levels 143 on crop yields (Easterling and Apps 2005; Izaurralde et al. 2003; Rosenzweig et al.
2004; Tao et al. 2003).
Studies of European agricultural systems conclude that there is strong evidence in climate change scenarios, especially for soils with low soil water storage capac- ity or no groundwater impact to the rooting zone, that irrigation or water-saving production techniques (e.g. by introducing mulching systems, adapting crop rota- tion), will remain important requirements in future climate conditions in Central European agricultural regions for crops to attain their yield potential (Eitzinger et al. 2003). Further they conclude that if the droughts frequency and duration in- crease further (Seneviratne et al. 2006; Pal et al. 2004) or soil and groundwater re- serves decrease (e.g. by decreasing summer river flow from Alpine region) drought damage will become more common. Summer crops will be more vulnerable and dependent on soil water reserves, as the soil water or higher groundwater tables during the winter period cannot be utilized as much as by winter crops. Evapo- transpiration losses during summer due to higher temperatures would increase significantly.
Negative yield effects for several crops and significant additional water use for irrigation (up to 60-90%) might be expected in the Mediterranean region (Marrac- chi et al., 2005; Tubiello et al., 2000) or regions with low soil water availability due to climate change. According to Olesen and Bindi (2002), reduced water availabil- ity in Mediterranean countries as a consequence of climate change and variability might be the most important climate risk for crop yields in Europe, especially if ex- treme weather events increase. A European study (EEA 2005) draws a similar con- clusion, remarking on the need for future studies on the effectiveness of irrigated agriculture in Southern Europe.
The results of climate change impact and adaptation studies in agriculture give us a good insight into the effects on agricultural production of the optimization of farm technologies and management. They suggest several potential measures for adaptation of farm technology and management to changing climatic conditions.
In many studies focusing on climate change impacts on crop production in tem- perate agricultural regions, only simple measures such as possible changes in sow- ing dates (earlier sowing dates) and cultivar selection (e.g. selecting slower matur- ing varieties) were investigated (Abraha and Savage 2006; Alexandrov et al. 2002;
Reilly and Schimmelpfenning 1999; Parry 2000; Sivakumar et al. 2005), showing that these measures often have the potential to significantly reduce negative im- pacts on crop yields (Alexandrov et al. 2002; Baethgen and Magrin 1995; Gbeti- bouo and Hassan 2005; Luo et al. 2003). Adaptation of planting density and fertil- izing can have similar effects (Holden and Brereton 2006; Cuculeanu et al. 1999).
Studies that focus more on adaptation confirm that simple and low-cost tech- nologies can effectively reduce the negative effects of climate warming scenarios and extreme weather on crop yields (Easterling et al., 1993, 1996; Salinger et al., 2005).
However, many adaptation measures to current or changing climates in crop and animal production depend on the availability and costs of different farm tech- nologies, related to the established agricultural system and socioeconomic and policy conditions (Giupponi et al. 2006). Technological research and development are among the most frequently advocated strategies for adapting agriculture to eli-
mate variability and change (Ewert et al. 2005; Perarnaud et al. 2005; Smithers and Blay-Palmer 2001).
In developed countries with high-input agriculture many farmers may be able to deal better with climate variability and change thanks to their available exten- sive "technological" tool-kit, but the long-term vulnerability and risk may increase as well (Bryant et al. 2000; Burton and Lim 2005). In low-input agricultural sys- tems, on the other hand, the individual farmers depend to a large extent on low- cost technologies or on external input such as institutional support for more costly technologies. The concept of low external inputs sustainable agriculture (LEISA), which is well described by Stigter et al. (2005), is probably the only realistic op- tion for many developing countries if they are to secure sustainable food produc- tion and welfare. Moreover, studies on climate change impacts on crops showed that there is enormous variability between areas (e.g. shown by Jones and Thorton (2003) for African maize production), which makes locally adapted technologies even more important.
In this paper we will try to give an overview of this complex picture by using ex- amples from selected countries with different climatic conditions and agricultural systems. Itdiscusses also the optimization of farm technologies as a means of en- suring sustainable agricultural production. This optimization may include stabi- lizing agroecosystems and providing an acceptable income for farmers.
10.2
Strategies for optimizing farm technologies in various agricultural systems
In order to analyse optimisation strategies in various agricultural systems con- sidering sustainability (Fig. 10.2.) we propose to make a distinction between the most important and climate-sensitive agricultural resources to be managed, such as water, soil (including nutrients), crop (including management) and microcli- matic conditions in relation to low, medium and high agricultural input systems.
Of course, many farm technology optimization strategies can affect more than one of these resources at the same time. Low-input systems may be characterized as small farm structures and with low income in a less developed socioeconomic en- vironment as is found in developing countries (almost no financial reserves for in- vestment in farm technologies available). Medium input systems might be char- acterized as small farm structures with acceptable farm income in a good socio- economic environment, as in small farms in Western Europe (limited financial reserves for investment in farm technologies available). High input systems might be characterized as farms with high income levels in any socioeconomic environ- ment, where there is theoretically no limitation to investment in new farm tech- nologies.
Chapter 10: Weather and climate and optimization offarm te(hnologies atdifferent input levels 145
Impact oflllnput" and IITechnologytl on sustainability
Fig.10.2. Types of farming systems in relation to technology used and trend in sustainability.
10.2.1
Optimization offarm technologies and water resources
Itis well known that on a global scale water is probably the most limited resource for agricultural production and directly sensitive to climate variability. Water re- sources can therefore vary strongly from year to year and within a single year. Ex- treme precipitation events and floods can be as devastating as droughts (Rosen- zweig et al. 2002; Chang 2002), and these extremes could increase under climate change, depending on the region. Extreme precipitation can further lead to nitro- gen leaching on sandy soils, which might be accelerated under increasing climate variability in more humid regions (Wessolek and Asseng 2006) and have implica- tions for agricultural land use and management for groundwater recharge harvest- ing, for example in northern Germany.
However, water shortage and droughts are the most important devastating fac- tors for agriculture and food production because of their large spatial extension, especially in many subtropical regions and developing countries. Over the centu- ries, mankind in semi-arid and arid regions have therefore developed technolo- gies or systems for water harvesting or irrigation. Nowadays known as traditional methods or indigenous techniques, they are still in use in many parts of the world, not least because they are well adapted to local conditions and are often the only
option because of their low costs or inputs. Examples are given in numerous publi- cations such as those listed by Stigter et al. (2005).
70.2.7.7
The roleof farm technologies in watermanagement in developed regions or countries
In many agricultural systems, mostly in better developed countries or regions, new technologies for water management have been successfully introduced and have increased agricultural productivity. For instance, irrigated agriculture in the Mediterranean area was introduced in ancient times and has been improved over time with experience. However, irrigation techniques have been kept in the same way for centuries in most Mediterranean countries. Inefficient flood irrigation sys- tems, for example, can be still found in many areas of Spain and Egypt (El Gindy et al. 2001; Neira et al. 2005). Modern sprinkler and drip-irrigation systems have been introduced at great expense in some Mediterranean European regions such as Spain (MAPA 2005). These new techniques significantly reduce water use. As can be seen in Fig. 10.3, the Spanish productivity of irrigated crops, such as maize, has increased in the last 15 years, compared with countries like Egypt, despite the fact that the total production is lower. The differences between Spain and Egypt may have many causes, but the new engineering irrigation infrastructures that have been introduced in Spain (ANPC 2003) certainly have a strong influence on this yearly yield increment.
4 -
B2
l:l!!
~1
"C
Q)
'S 0
~'0c:( -1
-2
-3
1990
...
1995 2000
y=0.7237x - 0.2666 R2=0.9101
...
... ...
2004
&IProd-Dif[JYield-Djf
Fig. 10.3. Absolute differences between Egyptian and Spanish maize production (in BT) and yield (in t/ha).
Chapter 10: Weather and climate and optimization offarm technologies atdifferent input levels 147 Water availability could well be the most important agricultural constraint in Mediterranean agriculture in the future (Olesen and Bindi 2002; EEA 2005) and in many other agricultural regions worldwide. Adaptation tests by Rosenzweig et al. (2004) for several major agricultural regions worldwide have shown that few regions can readily accommodate an expansion of irrigated land in a changed cli- mate, while others would suffer decreases in system reliability if irrigation areas had to be expanded. Timely improvements in crop cultivars, irrigation and drain- age technology and water management are therefore required. Farmers in southern Europe, for example, must realize that techniques such as the"deficit Irrigation"
should be considered as an option in the next decades, or irrigated agriculture will become unaffordable (Fereres 2005). Nevertheless, the success of deficit irrigation in a given year depends on weather behavior during that year (Farre 1998), which makes it difficult to introduce it into farming practice. The only practical solution for the extensive introduction of deficit irrigation and similar techniques to im- prove irrigation efficiency is through very local assessments, taking into account weather variability (Bastiaansen et al. 2004; Eitzinger et al. 2004; Utset et al. 2004;
Utset 2005; Fereres 2005).
As an example of medium- and high-input farming systems, irrigation is being modernised in Spain on a fairly large scale with governmental support (Beceiro, 2003; MAPA, 2005) to replace flooding by sprinkler and by other more efficient technologies.Itusually implies large investments and farmers cannot afford them on their own. However, irrigation must not only be kept but also enlarged if the Lisbon Strategy goals are to be met and rural living conditions improved (MAPA 2005).
Moreover, complete sprinkler coverage is very important in terms of person- nel savings. Southern European and Spanish agriculture is mainly based on family businesses. The rural population has dramatically decreased in Europe. Complete coverage combined with automatic control devices therefore allows the manpower effort involved in irrigation to be reduced to a minimum. Furthermore, irrigation advisers in the form oflocal specialists should be accessible to farmers to accom- pany modernization. These local services must be able to provide help to farmers in dealing with the new available technology. The irrigation advisers in Spain and other European countries usually have modern laboratories for soil property anal- ysis as well as a relatively dense network of agrometeorological stations and other high-input technologies. Besides, the specialists involved in such advice services could be trained in modern techniques such as simulation modeling tools and re- mote sensing interpretation.
Irrigation investments include channel designs, water distribution systems and pumping devices. The engineering effort involved is usually significant, costing several million euros. Complete sprinkler coverage usually involves underground PVC or metal tubes all over the agricultural field. Automatic control devices also need solar cells, modems, computer systems and other related technology. Fur- thermore, irrigation advice services call for government investment in trained per- sonnel, as well as laboratory infrastructures and technological facilities. Despite the large investment involved in these three potential measures, they can be am- ortized in few years, particularly in view of the anticipated increase in water prices in Europe as a result of political measures. The irrigation advice service could also