Vol.2, No.2, 68-77 (2011)
opyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
Agricultural Sciences
Diversity of shifting cultivation cycles among
small-scale farmers in Peruvian Amazon
Bohdan Lojka1*, Jan Banout1, Lucie Banoutova1, Vladimir Verner1, Patrick Van Damme2
1Institute of Tropics and Subtropics, Czech University of Life Sciences, Prague, Czech Republic;
2Laboratory of Tropical and Subtropical Agriculture and Ethnobotany, Ghent University, Ghent, Belgium;
*Corresponding Author: lojka@its.czu.cz
Received 25 November 2010; revised 16 February 2011; accepted 15 March 2011.
Although shifting cultivation is practiced by mil-
lions of farmers, it is often blamed for causing
deforestation and keeping farmers in poverty.
Our study focused on the Amazon basin, where
small-scale farmers widely practice shifting cul-
tivation. The objective w as to identify the diver-
sity in land use after initial slash-and-burn land
clearing among migrant peasants. Our research
aimed at documenting typical crop sequences,
plant species composition and specific lengths
of particular phases of shifting cultivation cy-
cles on the basis of farmers related field histo-
ries. Land use was examined in two settlements:
Antonio Raimondi and Pimental in Ucayali re-
gion, Peru. Data was gathered via semi-struc-
tured questionnaires that focused on the socio-
demographic characterization of agriculture-de-
pendent households and their land use charac-
teristics. More in-depth a ssessments of crop oc-
currence, cropping sequence and length of the
different shifting cultivation cycles were con-
ducted on 114 fields in Pimental and 44 fields in
Antonio Raimondi. Interview analysis showed
that in both villages, forest cover has substan-
tially decreased over the last 10 years. Results
also indicate considerable variation in swid-
den-fallow systems. Whereas settlers in Anto nio
Raimondi plant annual crops after slashing and
burning the forest, settlers in Pimental gave
more importance to perennial crops. Progress
in deforestation and land degradation is rela-
tively more pronounced in the younger settle-
ment (Antonio Raimondi). These differences are
likely caused by the different social back-
grounds of settlers and histories of each site.
Small-scale farmers in the study area are now
facing a problem with the transition from shift-
ing cultivation to sedentary farming. Farmers in
areas with a prevalence of annual cropping use
a significantly shorter fallow period, which causes
a higher rate of forest degradation. As annual
cropping seems to be unsustainable in relation
with forest degradation, farmers should either
use a longer natural fallow to sust ain longer cro -
pping cycles, or shift to tree-based land use sy-
Keywords: Agroforestry; Deforestation; Land
Degradation; Slash-And-Burn; Swidden-Fallow
Despite rapid economic development in many tropical
countries, shifting cultivation is practiced by millions of
farmers and has been blamed for causing deforestation
and keeping farmers in poverty [1]. Exact figures about
the total area under shifting cultivation are not available,
but it is still applied in at least some 40 - 50 countries [2];
and shifting cultivation constitutes an important part of
the 850 million hectares of secondary forest manage-
ment in tropical Africa, America and Asia [3]. Some
researchers have claimed that shifting cultivation is
practiced on as much as 30% of the world’s exploitable
soils [4]. Figures for the number of people depending on
this system are also uncertain and range between 40 to
500 million [4-7].
Slash-and-burn agriculture can only be sustainable
when population densities are low enough to allow re-
establishment of the forest within slash-and-burn fields.
However, under the pressure of increasing populations,
fallow periods are drastically reduced and the system
degrades, resulting in serious soil erosion and a decline
in soil fertility and productivity [8]. This assumption is
commonly accepted, however, empirical evidence is
scarce. Mertz et al. [1] have demonstrated that fallow
length is a weak predictor of crop yields and that other
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. Openl y accessible at http:// www.scirp.org/journal/AS/
factors such as fertilizer inputs, drought, flooding or
pests and diseases are more important determinants of
yield. Thus, fallow length is not the best proxy for as-
sessing sustainability of the system.
Shifting cultivation is thought to account for about
one third of deforestation in the Amazon, while cattle
ranching is responsible for at least half of the forest re-
treat [9]. After the annual crop stage of the slash-and-
burn cycle, farmers leave the land for short fallow, or
convert is to other uses, including pastures for cattle and
perennial crops [10].
Although a relatively large amount of literature has
been generated on the subject, a number of aspects of the
system is still poorly understood [1]. More applied re-
search to explain local complexities of the system and to
demonstrate to what extent shifting cultivation contrib-
utes to local livelihoods and environmental (mis)mana-
gement is still needed.
Our study focused on the slash-and-burn system in the
Ucayali region of the Peruvian Amazon. Between 1999
and 2005, disturbance and deforestation rates throughout
the Peruvian Amazon averaged 632 and 645 km2·yr–1,
respectively, whereby 64% of all damage was concen-
trated in the area around the Ucayali logging centre of
Pucallpa and along the road network emanating from it
[11]. In this region, colonists or migrating landless pea-
sants lacking the traditional knowledge required for
maintaining sustainability of their shifting cultivation
system predominate. Generally, crop yields are decreas-
ing and soil degradation is rapidly increasing. On such
degraded land extensive grasslands have developed, do-
minated by Imperata spp. The latter is considered to be
one of the world's worst weeds and a reliable indicator
of land degradation [12,13]. These grasslands are mostly
formed following annual bushfires that hinder the re-
generation of woody vegetation [14]. Such landscape is
considered as the final stage in the process of land deg-
radation with an irreversible loss of forest cover and a
permanent loss of agricultural income [15].
Our objective was to identify the diversity in land use
after initial slash-and-burn among migrant peasants and
to identify traditional technologies used in the cropping
cycles (from original forest, through cropping sequence
to secondary fallow), in order to understand the factors
influencing the changes in local agricultural systems.
Our research aimed at documenting and characterising
typical crop sequences, plant species composition and
lengths of particular phases of shifting cultivation cycles
on the basis of collecting data about field history. Th-
rough this documentation, we can quantify how local
households change original natural environment on their
farming land. One of the most striking features of land
use practices in tropical environments is their great di-
versity (use of plant species, varieties, cropping se-
quences). Therefore, by examining local differences,
such research could provide valuable information about
the varied economic opportunities, constraints on pro-
duction, and land use decisions perceived by local farm-
ers [16]. On the basis of these findings, new alternative
land use methods can be proposed in order to improve
sustainability of their farming.
2.1. Site Description
Pucallpa, the capital of Ucayali region, is situated on
the Ucayali River, 860 km from Lima, the capital of
Peru, at 154 m above sea level, 8°23' S and 74°31' W.
Ucayali region borders Brazil to the east. Annual rainfall
ranges 1500 - 3000 mm (with rainfall increasing in a
western direction) with a mean annual precipitation of
approximately 1600 mm around Pucallpa. Intense pre-
cipitation prevails during the wet months from February
to May and from September to November [17]. Average
annual temperature is around 25˚C, with a maximum of
31˚C and a minimum of 19.5˚C. Soils include more fa-
vourable alluvial, seasonally-flooded riverine system
entisols, where pH is about 7.7, available P is 15 ppm
and upland, well-drained ultisols of forested areas with
an acid pH around 4.4 and low in P (around 2 ppm) [17].
In general, these soils have low quality for agriculture
[18]. The upland terrain is usually flat or undulating. The
original, natural vegetation is a tropical semi-evergreen
seasonal forest, now mixed with palm forest, dominated
by Mauritia spp. palms. Settlement around Pucallpa
started in the 1940s after construction of the road linking
the cities of Pucallpa and Lima, and was promoted by
road improvements in the late 1960s.
For our study, two representative settlements (Antonio
Raimondi and Pimental), located near the city of Pu-
callpa, were chosen. Both villages are situated in the
Campo Verde district, which came into existence in 1982,
and are connected with the Lima-Pucallpa highway. An-
tonio Raimondi is located 25 km west of Pucallpa. Ac-
cording to the head of the local municipality, this com-
munity was established in 1990 and, in 2005, there were
27 households (about 200 inhabitants). Due to slash-and-
burn farming, most of the forest has already been cut
down and vast areas around the village are degraded and
covered by Imperata grass. Farmers establish their fields
either on already degraded plots, or else they go further
to clear the primary or secondary forest and open a new
field. Secondary forest (so-called purma) is a previously
cultivated area that was left under fallow for 25 - 40
years. The most important crop is cassava (Manihot es-
culenta), which is considered the only crop which can be
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. http://www.scirp.org/journal/AS/Openly accessible at
economically grown on degraded land infested by Im-
perata. Cassava mainly serves for household subsistence,
but is often sold on the local market in Pucallpa as well.
Other staple crops are rice (Oryza sativa), maize (Zea
mays), bananas, plantains (Musa spp.) and cowpea (Vi-
gna ungiculata), mainly grown on fields with better soil
fertility, and usually planted after slashing and burning
the secondary forest. In addition, nearly each household
is surrounded by a homegarden with many fruit and
timber trees mixed with vegetable and medicinal plants.
Local households also depend on collecting non-timber
forest products (medicinal plants, honey and fruit) from
adjacent forests, whereas they also fish and hunt. All these
products are sold on the local market in Pucallpa, which
can be reached within one hour by local transport. How-
ever, this transport is expensive. Farmers usually own a
few heads of cattle (on average 2 - 3 heads), sometimes
pigs and horses, and most only raise poultry. They have
very limited opportunity for any off-farm employment.
The second village, Pimental, located 35 km west of
Pucallpa, is not very different from the previous site, but
the community is older (established in 1972) and more
prosperous, as farmers are more focused on cash crop
growing. This community was established when the hi-
ghway linking Lima with Pucallpa was improved in the
1970s. There were 56 households (about 400 inhabitants)
in 2005. Large areas are covered by weedy grassland
species such as Imperata spp. and Brachiaria spp. The
land use system is based on the same methods of slash-
and-burn farming, although cultivation of the more eco-
nomically-viable pepper (Piper nigrum) has a tradition
in this zone. Farmers also grow (semi-) perennial crops
such as pineapple (Ananas comosus), native fruit tree
species and various citruses (Citrus spp.). Furthermore,
settlers also have more opportunities for off-farm in-
come generation.
2.2. Data Collection and Evaluation
Our methodology of data collection and evaluation
was based on the similar study of Coomes and Burt [16]
made in traditional community near Iquitos, Peru. In the
period from June to October 2005, a survey was con-
ducted in both above-mentioned villages. Data on gen-
eral household characteristics were collected via semi-
structured interviews with local farmers. In each village,
a sample of households practicing agriculture as their
main activity was randomly chosen. Altogether, 27
households were interviewed: 11 in Antonio Raimondi
(40% of total number of households) and 16 in Pimental
(29%). The questionnaire was usually filled in by the
household head, typically a male. The household inter-
view focussed on demographic characteristics (e.g. size
and composition through time), methods of shifting cul-
tivation used, history of their agricultural practice, basic
socio-economic data and additional information related
to main crops and trees grown, land tenure and problems
with agriculture. In addition, each respondent was ac-
companied to each of his/her fields where we assessed
vegetation type, field size, crop composition and previ-
ous use. Each visit started with an initial delineation of
the whole farm area. Then the area was divided into
smaller parts according to current vegetation type and
crop composition. The history of each field was recon-
structed by asking the respondent to recall type and dura-
tion of each crop and forest fallow, beginning with pre-
sent field cover and working backward through time. A
total of 163 and 94 fields were thus inventoried Pimental
and Antonio Raimondi, respectively. Generally, farmers
were able to recall most of their experiences over the
time they had lived in their particular location, though
occasionally with some difficulty. By knowing crop/fal-
low durations in the sequence back through time, we
were able to reconstruct, using manual spreadsheet, the
history of each field held by the respective farmer. Based
on this, data we were able to calculate various current and
past land-use system sizes, their proportion of total farm-
ing land, and assess the changes in time. The data served
for identification of several shifting cultivation cycles and
determination of the most frequently planted crop and
tree species. We used the independent two-sample t-test
to reveal the statistically significant differences between
both settlements. Household and field surveys afford a
comprehensive and systematic analysis of variation and
diversity in local shifting cultivation systems.
3.1. General Household and Farm
Respondents have been living, on average, for 13 and
18 years in Antonio Raimondi and Pimental, respectively.
In Pimental, 56 of respondents were born (or had lived)
there since the community was established. Each house-
hold consists of, on average, four to five members (Ta-
ble 1). On average, three household members work on a
farm as their main activity (child labour was not counted
but occurs). Average farm size is about 20 ha. We tried
to assess farm size changes over the last 10 years. Only
respondents living in their village since before 1995
were included in this attribute, 8 households from Anto-
nio Raimondi and 9 from Pimental. For simplification,
this group of respondents will be further referred to as
“old residents”. In both villages, farm size has slightly
decreased over the last 10 years. There is an increasing
trend in acquiring land tenure rights over this period.
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
Table 1. Household demography and land availability in Antonio Raimondi and Pimental.
Unit Pimental Antonio Raimondi T-test (0.05)
Mean SD Mean SD p
Total members of household* pers. 4.81 ± 1.91 4.09 ± 1.22 0.279
Age of household head* year 43.2 ± 13.7 49.4 ± 15.9 0.291
Farm size actual* ha 18.5 ± 11.0 20.7 ± 13.4 0.645
Farm size per family member* ha 4.7 ± 4.10 5.4 ± 3.81 0.645
Farm size 10 years ago** ha 21.4 ± 8.55 24.1 ± 12.5 0.243
% of fields with land tenure actual* % 84.8 75.6
% of fields with land tenure 10 years
ago** % 82.0 46.1
*Values for all sampled respondents in Antonio Raimondi (n = 11) and Pimental (n =16); **Values only for sampled older respondents living
in Antonio Raimondi (n = 8) and Pimental (n = 11) since before 1995.
Currently, more than 84 of the total area in Pimental
and 75 in Antonio Raimondi is protected by land ten-
ure rights. Especially in Antonio Raimondi, private land
ownership has increased significantly over the last 10
years, although almost one fifth of all respondents in
Pimental and one third in Antonio Raimondi does not
have any land tenure rights at all.
3.2. Land use Classification and Changes
Based on farmers’ responses, we identified nine dif-
ferent land use system, based on current plant species
composition and use (Table 2). According to this classi-
fication, we assessed changes in land use within both
villages over the last 10 years (Table 3). In 1995, a total
of 64% of the farm land in Pimental was forested (re-
sidual forest or fallow) or covered by tree-dominated
land use systems (tree crop plantation, agroforestry and
homegardens); 36% was covered by pastures and only
small parts were cropped by non-wood crops (3%), or
were degraded (2%). In Antonio Raimondi, 73% of the
farmed land was forested or covered by tree-dominated
land use systems in 1995; pastures and degraded land
covered 13% and 11%, respectively; only 3% was
cropped by non-wood crops. Differences between vil-
lages could be explained by the fact settlements in Pi-
mental are older and so that farmers had already defor-
ested higher proportion of their land.
After 10 years, there has been an important decrease
in forested land in both villages. In Pimental, reduction
in forested area amounted to 23% whereas in Antonio
Raimondi it reached as much as 47%. Currently, forests
and fallows cover only 21% and 11% of farm land in
Pimental and Antonio Raimondi, respectively. In both
villages, we see the same trend of land use transition:
decrease in forest cover and increase in grass cover, evi-
denced by higher proportion of pasture and degraded
land (44% increase in Antonio Raimondi). Generally,
land classified as pasture is used extensively having very
low stocking rate. During this period, there have been
only slight changes in proportion of farming area occu-
pied by young fallow, homegardens, tree plantation,
agroforestry systems and non-wood crops. It seems that
households did not increase their total cropped extension
substantially over the last 10 years.
3.3. Field Characteristics and
Swidden-Fallow Cycles
A total of 163 and 94 fields were studied for assess-
ment of current land use and specific shifting cycles in
Pimental and Antonio Raimondi, respectively (Table 4 ).
Each household in the sample possesses a collection of
plots in different phases, which, together, represent its
swidden-fallow agroforestry portfolio. On average, ho-
useholds in Pimental hold a total of 10 plots (7 in crops,
1 in forest or fallow and 2 under pasture or degraded
land). About 27% of household land holding is currently
used for annual or perennial cropping, 20% is forested or
under fallow, whereas the remaining 53% is pasture or
degraded land. Households in Antonio Raimondi hold,
on average, a total of 8 plots (5 in crops, 1 in forest or
fallow and 2 under pasture or degraded land). Nearly
20% of household land holdings is used for cropping,
11% is under forest or fallow; the remaining 69% is
pasture and degraded land. It is evident that land in An-
tonio Raimondi is currently more deforested and de-
graded than in Pimental.
Altogether, 87 complete swidden-fallow cycles were
documented from the field histories in Pimental: 62
fields were claimed from residual forest, 16 originated
from old fallow, 4 from young fallow, whereas the re-
maining 5 fields were established from pasture. We
identified seven principal cropping cycles established
after slashing and burning of residual forest (Figure 1)
and four most frequent crops; i.e. rice, cassava, banana
and pepper. After clearance, the deforested land was
used for planting various crops. Rice and pepper inter-
planted with bananas were first planted on 51% and 41%
of all fields, respectively. On the remaining 8% of fields,
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
Table 2. Classification of land use systems.
Land use type Local name Characteristics
Residual forest Monte
An old primary forest that was not slashed and burnt in recent history but can
be used for timber, game, medicinal plants and fruit collection. People often
refer to monte alto or monte virgen. Monte virgen is considered as a virgin
forest untouched by timber exploitation while monte alto is a logged-over
forest, but never slashed or burnt.
Old fallow Purma alta
High-grown secondary forest 6 years old or more, which was formerly
slashed and burnt and which has continuously turned into a secondary forest
over time.
Young fallow Purma baja Young secondary forest up to 5 years old.
Tree plantation Plantación Plantation of citruses, native fruit trees or timber trees.
Agroforestry Agroforestería Plots covered by trees and/or shrubs along with non-wood annual or perennial
Homegardens Huerto familiar Plots adjacent to the house consisting of a mix of annual and semi-perennial
plants and trees with different uses, mainly for household consumption.
Non-wood crops Chacra Annual crops such as cassava, maize, rice, vegetable etc. and non-wood per-
ennials such as pineapple, banana and plantains, pepper (Piper nigrum).
Pasture Pasto Plot assumed to be entirely used for livestock. It is covered with other grasses
than Imperata spp., like Brachiaria spp. etc.
Degraded land Pasto degradado Plots covered by noxious grassy weeds, mainly Imperata spp.
Table 3. Land use ( area) and total area of specific land use type in 1995 and 2005.
Pimental Antonio Raimondi
1995** 2005* Difference1995** 2005* Difference
[ha][%] [ha] [%] [%] [ha][%] [ha] [%] [%]
Residual forest 29.814 22.5 8 –6 47.027 12.05 –22
Old fallow 59.528 34.5 12 –16 49.8 29 7.0 3 –26
Young fallow 5.0 2 3.6 1 –1 4.252 6.0 3 1
Tree plantation 26.512 36.6 12 0 12.87 10.55 –2
Agroforestry 10.25 20.4 7 2 10.06 14.36 0
Homegarden 5.8 3 6.9 2 –1 3.0 2 6.0 3 1
Non-wood crops 6.5 3 14.4 5 2 4.853 15.47 4
Pasture 68.332 140.0 47 15 23.613 76.033 20
Degraded land 4.0 2 17.5 6 4 18.811 80.935 24
*Values for all sampled respondents in Pimental (n=16) and Antonio Raimondi (n=11). ** Values only for sampled older respondents
living in Pimental (n = 11) and Antonio Raimondi (n = 8) since before 1995.
Table 4. Field size by land use type in 2005.
Pimental Antonio Raimondi
No. of
(ha) Range (ha)No. of
(ha) p
Residual forest 4 22.5 5.63 ± 6.610.5 - 15.04 12.03.00± 4.06 0.5 - 9.0 0.524
Old fallow 10 34.5 3.45 ± 2.701.0 - 9.55 7.0 1.40± 0.82 0.5 - 2.5 0.127
Young fallow 4 3.6 0.89 ± 0.830.06 - 2.03 6.0 2.00± 1.73 1.0 - 4.0 0.305
Tree plantation 46 36.6 0.79 ± 0.720.1 - 4.510 10.51.05± 0.95 0.25 - 3.3 0.334
Agroforestry 31 21.7 0.70 ± 0.670.18 - 3.014 14.31.02± 0.65 0.25 - 2.0 0.146
Homegarden 14 6.9 0.49 ± 0.330.1 - 1.09 6.0 0.67± 0.25 0.5 - 1.0 0.190
Non-wood crops 26 13.6 0.52 ± 0.510.02 - 2.023 14.40.63± 0.79 0.1 - 4.0 0.585
Pasture 22 141.0 6.40 ± 6.810.5 - 25.012 75.96.33± 4.48 0.7 - 13.0 0.975
Degraded land 6 17.5 2.92 ± 2.010.5- 5.0 14 80.95.78± 5.96 0.1 - 17.0 0.272
Total 163 298.0 94 227.0
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. http://www.scirp. org/journal/AS/
Figure 1. Typical swidden-fallow cycles on fields in Pimental village after clearing of the forest (No. of
fields 87, no. of cycles 7, no. of crops 4, mean cycle length 12 years, mean fallow length 6 years).
other crops such as maize, pineapple, sugar cane or
vegetables were planted. After harvesting rice subsequent
crops planted were typically cassava, banana/ plantain,
cowpeas or again rice. The second most common cycle
started by an initial crop mixture of pepper with bananas.
Pepper is grown for 8 years on average; at the end of this
cycle, the field is usually left to pasture, tree plantation,
or fallow. In general, one cycle length varied from 1.5 to
27 years, with a mean duration of 6 years of fallow and a
mean total cycle length of 12 years. The shortest cycle
was “rice-short fallow-rice” with a minimum of 18
months and a mean duration of 2.7 years.
In Antonio Raimondi, 48 complete swidden-fallow
cycles were identified from the field histories: 28 fields
were established from forest, 9 originated from old fal-
low, 8 from degraded land whereas 2 fields were estab-
lished from pasture. We identified eight principal crop-
ping cycles established after slashing and burning of
residual forest (Figure 2) and five most frequent crops;
i.e. rice, cassava, banana, maize and cowpea. Rice and
cassava/banana were planted on 56% and 31% of all
fields originating from forest, respectively. Rice (56%),
cassava/bananas (31%) and maize/cowpeas (12%) were
the first crops to be grown after forest clearance. After
rice, crop mixtures that followed were typically cas-
sava/banana (33%) and maize/cowpea (11%); 45% of
the land was left fallow; and pasture was established in
11% of the cases. In addition to rice, cassava/bananas
were also grown as the first crops after forest clearing.
Very often, farmers repeat planting of a cassava/banana
mixture subsequently for several years. Cycle length
varied from 17 months to 10 years, with a mean duration
of 3 years of fallow and a mean total cycle length of 5
years. The shortest cycle was “rice - short fallow - rice”,
with a minimum duration of 17 months. In both villages,
the final land use system in the cycle is either tree-based
(fallow, tree plantation or agroforestry) or, as in the ma-
jority of cases, the soil is so severely depleted and is left
as a low-grade pasture or degraded land without any
economic use.
3.4. Crop and Tree Species Diversity
A total of 100 tree and crop species (90 in Pimental
and 55 in Antonio Raimondi) were found on 158 fields
(114 in Pimental and 44 in Antonio Raimondi). The
largest variety of species was encountered in tree planta-
tions (70 and 37 species in Pimental and Antonio Rai-
mondi, respectively). Plots with non-wood crops were
generally the least diverse (13 and 16 species in Pimen-
tal and Antonio Raimondi, respectively). Despite the rich
overall diversity of crops observed across fields, most
individual plots contained relatively high densities of a
small number of crops. As farmers mentioned, banana,
cassava, pineapple and rice are the most widely planted
crop species, whereas citruses, guaba (Inga edulis) and
peach palm (Bactris gasipaes) are the most widely
planted tree species (Table 5).
In both villages, it was observed that, over the last 10
years, mean farm size decreased while percentage of
land with secure tenure significantly increased. Shifting
cultivation patterns are different in each settlement. In
both villages, we found a large decrease in forest cover
over the last 10 years. In 1995, residual forest covered
14% and 27% of farmers’ fields in Pimental and Antonio
Raimondi, respectively, while 30% and 31% of farm
land, respectively, was kept fallow. Fujisaka and White
[10], while conducting their study around Pucallpa in
Openly accessible at
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
Figure 2. Typical swidden-fallow cycle on fields in Antonio Raimondi village after clearing of the forest.
(No. of fields 48, no. of cycles 8, no. of crops 5, mean cycle length 5 years, mean fallow length 3 years).
Table 5. Most frequently cultivated crop and tree species on fields in Pimental (PIM) and Antonio
Raimondi (AR).
Vernacular name Scientific name Product Frequency of occurrence
Total PIM AR
(n = 158)(n = 114) (n = 44)
Crop species
Banana Musa spp. Fruit 42 26 16
Cassava Manihot esculenta Tuber 40 22 18
Rice Oryza sativa Grain 25 12 13
Pepper Piper nigrum Condiment 21 21 0
Pineapple Ananas comosus Fruit 20 12 8
Sugar cane Saccharum o fficinarum Juice/sugar 15 8 7
Coca Erythroxylum coca Stimulant 8 6 2
Cocona Solanum sessiliflorum Fruit 8 0 8
Bijao Calathea sp. Vegetable 7 7 0
Cowpea Vigna ungiculata Bean 7 4 3
Maize Zea mays Grain 7 4 3
Tree species
Citrus Citrus spp. Fruit 88 75 13
Guaba Inga edulis Fruit 38 23 15
Peach palm Bactris gasipaes Fruit 33 27 6
Caimito Pouteria caimito Fruit 22 12 10
Tahuari Tabebuia sp. Timber 21 18 3
Sangre de grado Croton l ech le ri Latex 20 18 2
Caoba Swietenia macrophylla Timber 19 15 4
Cedro Cedrela odorata Timber 19 15 4
Mango Mangifera indica Fruit 19 8 11
Aguaje Maurici flexuosa Fruit 15 11 4
Umari Pouraqueiba sericea Fruit 13 11 2
Capirona Calicophyllum
spruceanum Timber 13 10 3
Ishpingo Amburana clarensis Timber 13 10 3
Shebon Scheelea bassleriana Thatch 12 10 2
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. http://www.scirp. org/journal/AS/Openly accessible at
Bolaina Guzama crinita Timber 13 8 5
Carambola Averrhoa carambola Fruit 11 8 3
Anona Rollinia mucosa Fruit 9 5 4
Coconut Cocos nucifera Nut 9 5 4
Camu-camu Myrciaria dubia Fruit 8 7 1
Macambo Theobroma bicolor Fruit 8 5 3
Mamey (poma
rosa) Syzygium sp. Fruit 8 7 1
Avocado Persea americana Fruit 8 7 1
Shimbillo Inga spp. Fruit 8 7 1
Guanabana Anona muricata Fruit 7 5 2
1996, found slightly higher numbers: 27% forest and
39% fallow. In 2005, about 12% of the land was covered
by forest, 13% by fallow and 53% by grass vegetation
(pasture and degraded land) in Pimental, whereas only
about 5% was forest, 6% fallow and about 68% grass
vegetation in Antonio Raimondi. Furthermore, in Pi-
mental we find more tree plantations (either fruit or tim-
ber trees) than in Antonio Raimondi. This is probably
due to the divergent histories of the sites. Pimental was
established immediately after timber exploitation of the
forest by logging companies, whereas Antonio Raimondi
was established as a consequence of increasing popula-
tion pressure in Pucallpa. It would seem that, in the older
Pimental settlement, cultivation has acquired more per-
manent character and whereas land use systems are
based on tree cultivation, especially of citruses.
Even though the ratio of land degradation and forest
destruction in 1995 was higher in Pimental, further de-
forestation proceeded relatively slowly, as compared to
what happened in Antonio Raimondi. This could proba-
bly be explained by a relatively better agricultural and
socio-economic situation in Pimental. In the letter com-
munity, planting of pepper and fruit trees has a long tra-
dition and this makes the village more prosperous. As a
consequence, settlers prefer long-term plantation crops,
while in Antonio Raimondi they prefer annual or
short-term perennial crops.
We found that shifting cultivation cycles are very di-
verse in our study area from the points of view of cycle
length, plot and crop composition. In both villages, basic
cycle components are staple crops such as rice, cassava,
banana, maize and cowpeas. In Pimental, farmers also
grow pepper, but the mean length of a complete shifting
cultivation cycle there was 12 years, while in Antonio
Raimondi it was only five years. We also found that
mean duration of fallow in Pimental is twice as long (six
years, as compared to three years in Antonio Raimondi).
Although Mertz et al. [1], in their case study from Kali-
mantan, wrote that fallow length is a weak predictor of
crop yield (and thus sustainability of the system), we
found a positive relationship between the length of the
fallow and the length of the subsequent cropping period.
When fallow period is longer, subsequent cropping can
also be longer and more diversified. It seems that larger
area taken by pastures and degraded land in Antonio
Raimondi could be a consequence of a shorter fallowing
period and the subsequent rapid weed proliferation and
soil degradation.
According to Boserup [19], shifting cultivation sys-
tems usually evolve toward “annual cropping” and
“multiple cropping” systems through a progressive re-
duction in fallow length and fire intensity. Woody vege-
tation is eliminated from the fields and interplanting of
trees and crops only occurs in the later stages of intensi-
fication, when there is no more space to establish a pure
plantation. The small farmers around Pucallpa now find
themselves in this transition period. The question arises
whether the system of annual cropping can be sustained
in such an environment of low soil fertility and noxious
weeds. It seems that fallowing remains a very important
part of the local shifting cultivation cycle, but a transi-
tion to more intensified land use systems could be
achieved through tree-based systems such as perennial
fruit or timber tree plantations, or an agroforestry mix-
ture. These systems could substitute for the biological
role of natural fallow (soil fertility maintenance and
weed control) and bring the farmers the necessary return
on their investment (fruit, timber and non-timber prod-
ucts). Development agencies should not provide farmers
with complete, fixed technological packages, but should
design technologies in a less specific manner, thus al-
lowing for flexibility in their appropriation by farmers
Based on our results, we can conclude that, although
land use patterns after initial slash-and-burn were similar
in both study areas, considerable local diversity as well
as variations in principal crop composition and fallow
length occur in local shifting cultivation system. This is
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
due to the different backgrounds and histories of the
settlers. The rate of land degradation and forest conver-
sion to other uses is much higher in the more re-
cently-established settlement as a consequence of popu-
lation pressure and population structure, consisting pre-
dominantly of migrant peasants. Due to this fact and the
shorter fallow period (lack of perennial cropping tradi-
tion), the process of forest destruction is much more
pronounced in Antonio Raimondi than in the older study
site. Small-scale farmers in both study areas are now
facing a problem with the transition from shifting culti-
vation to sedentary farming.
The settlement where cultivation of market-oriented
perennials was introduced by its founders seems to be
permanent and more sustainable. The rate of forest de-
struction and land degradation is relatively slower in
settlements where perennials are planted than in settle-
ments where annual crops prevail. Fallow length is pri-
marily influenced by the type of principal crop composi-
tion and access to available land. Farmers focused
mainly on annual cropping employ a significantly
shorter fallow period and thus higher rate of forest deg-
radation occurs. As annual cropping seems to be unsus-
tainable, farmers should either continue using a longer
natural fallow period to sustain longer cropping cycles,
or shift to perennial tree-based land use systems that
require a higher initial investment, but brings larger
benefits in the future. Moreover, according to our study,
farmers in the study area use a considerable variety of
useful tree species; this could be an advantage for wider
use of them. We have to agree with the hypothesis pre-
sented by Fujisaka and White [10], that diminishing
pioneer conditions favour mixed systems that include
perennial crops with high-value products (e.g. coffee,
cocoa, fruit, timber). However, there is the risk of failure
of such an establishment as promoted by development
projects, when market projections are incomplete.
This research was conducted with financial support from the Foun-
dation Nadání Josefa, Marie a Zdeňky Hlavkových, Czech Republic,
Youth Activity Fund Of Explorers Club, USA and the Czech Ministry
of Agriculture within the Czech Republic Development Cooperation
program, project number 23/MZE/B/07-10.
[1] Mertz, O., Wadley, R.L., Nielsen, U., Bruun, B.T., Col-
fer, C.J.P., de Neergaard, A., Jepsen, M.R., Martinussen,
T., Zhao, Q., Noweg, G.T. and Magid, J. (2008) A fresh
look at shifting cultivation: Fallow length and uncertain
indicator of productivity. Agricultural Systems, 96 , 75-84.
[2] Mertz, O. (2009) Trends in shifting cultivation and the
REDD mechanism. Current Opinion in Environmental
Sustainability, 1, 156-160.
[3] FAO. (2005) State of the World’s Forest. Food and Ag-
riculture Organization of the United Nations, Rome,
[4] Warner, K. (1991) Shifting cultivators—Local technical
knowledge and natural resource management in the
humid tropics. Food and Agriculture Organization’s
Community Forestry Note, 8, Rome, Italy.
[5] Russell, W.M.S. (1988) Population, swidden farming and
the tropical environment. Population and Environment,
10, 77-94. doi:10.1007/BF01359134
[6] Kleinman, P.J.A., Pimentel, D. and Bryant, R.B. (1996)
Assessing the ecological sustainability of slash-and-burn
agriculture through soil fertility indicators, Agronomic
Journal, 88, 122-127.
[7] Sanchez, P.A., Palm, C.A., Vosti, S.A., Tomich, T. and
Kasyoki, J. (2005) Alternatives to slash and burn. Ch-
allenges and approaches of an international consor- tium.
In: Palm, C.A., Vosti, S.A., Sanchez, P.A. and Ericksen,
P.J. Eds., Slash-and-Burn Agriculture. The Search for
Alternatives, Columbia University Press, New York,
[8] Nair, P.K.R. (1993) An introduction to agroforestry.
Kluwer Academic Publishers, Dordrecht, The Nether-
[9] Serrao, E.A.S., Nepstad, D. and Walker, R. (1996) Up-
land agricultural and forestry development in the Am-
azon: sustainability, criticality and resilience. Eco-
logical Economics, 18, 3-13.
[10] Fujisaka, S. and White, D. (1998) Pasture or permanent
crops after slash-and-burn cultivation? Land use choice
in three Amazon colonies. Agroforestry Systems, 42,
45-59. doi:10.1023/A:1006195810077
[11] Olivera, P.J.C., Asner, G.P., Knapp, D.E., Almeyda, A.,
Galván-Gildemeister, R., Keene, S., Raybin, R.F. and
Smith, R.C. (2007) Land use allocation protects the
peruvian amazon. Science, 317, 1233-1237.
[12] Holm, L.G., Plucknett, D.L., Pancho, J.V. and Herberger,
J.P. (1997) The World’s Worst Weeds: Distribution and
Biology. University Press of Hawaii, Hawaii, USA.
[13] Garrity, D.P., Soekardi, M., De La Cruz, R., Pathak, P.S.,
Gunasena, H.P.M., Van So, N., Huijin, G. and Majid,
N.M. (1997) The Imperata grasslands of tropical Asia:
area, distribution, and typology. Agroforestry Systems, 36,
3-29. doi:10.1007/BF00142865
[14] Hartemink, A.E. (2001) Biomass and nutrient accumu-
lation of Piper aduncum and Imperata cylindrica fallows
in the humid lowlands of Papua New Guinea. Forest
Ecology and Management, 144, 19-32.
[15] Albers, H.J. and Goldbach, M.J. (2000) Irreversible
ecosystem change, species competition, and shifting
cultivation. Resource and Energy Economics, 22, 261-
280. doi:10.1016/S0928-7655(00)00034-8
[16] Coomes, O.T. and Burt, G.J. (1997) Indigenous market-
oriented agroforestry: Dissecting local diversity in we-
stern Amazonia. Agroforestry Systems, 37, 27-44.
B. Lojka et al. / Agricultural Sciences 2 (2011) 68-77
Copyright © 2011 SciRes. http://www.scirp. org/journal/AS/Openly accessible at
[17] Fujisaka, S., Escobar, G. and Veneklaas, E. (1999) Plant
community diversity relative to human land uses in an
Amazon forest colony. Biodiversity Conservation, 7,
41-57. doi:10.1023/A:1008855612209
[18] de Jong, W. (1995) Diversity, variation and change in
Ribereno agriculture and agroforestry. Doctoral Thesis,
Wageningen University for Life Sciences, The Nether-
[19] Boserup, E. (1965) The Conditions of Agricultural Gr-
owth: The Economics of Agrarian Change Under Po-
pulation Pressure. Earthscan Publication Ltd., London.
[20] Pollini, J. (2009) Agroforestry and the search for alterna-
tives to slash-and-burn cultivation: From technological
optimism to a political economy of deforestation. Agri-
culture, Ecosystems and Environment, 133, 48-60.