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Natural Resources Management in the
Matape Watershed
Hector M. Arias, Christopher Watts, David Peiia,
Gonzalo Luna, Maria L. Fernandez, Martin Reyes1
ABSTRACT
The Matape Mission, in the Upper Matape Watershed, has the
oldest record in ranching in the Arizona Sonora Desert, that covers
northwestern Mexico and southwestern United States (there are
historic records from 1670 showing that this area supplied animal
food to central Mexico).
The project has four stages: (1) resource inventory, (2)
information analysis, (3) experimentation of solutions that would
provide sustainable development, and (4) application of a regional
program. This paper only includes the first two stages, although the
third stage is in the preliminary phases.
The initial stage of the project involves the resource inventory
using available map information to build databases on Geographic
Information Systems. As a result, the watershed was divided in two
parts, the upper part is mainly rangeland, and the lower part is
mainly agricultural lands combined with rangelands. In the second
phase of the project, land deRradation phenomena were analyzed,
and erosion was found· to be one of the main problems in the upper
Matape Watershed, while salinity and saline intrusion were related to
low productivity of the lower part.
Erosion control measures along with techniques to improve the
range productivity is the challenge for the following stage of the
project. To do that, communication with farmers is required to
obtain a sustainable development.
INTRODUCTION
The state of Sonora in northwestern Mexico is traditionally considered a cattle raising state. It
was established as an important economic activity since 1670 when father Daniel Angelo Marras,
Rector of the Matape Mission, set the basis for this activity in Sonora. According to records from
1680-1682, the mission sent 5 000 cow~/y.- ~o central Mexico (Atondo et al, 1985). Since then,
livestock is the largest economic activity, in terms of area. Navarro et al (1986) mentioned that
about 78.44% of Sonora has cattle on a temporal (6.3%) or continuous basis (71.11), plus areas
with introduced species (1.04%), mainly buffel and Lehman love grasses. According to a land use
1
Institute del Medio Ambiente y Desarrollo Sustentable del Estado de Sonor~ Reyes y
Aguascalientes, Esq., Col. San Benito; Hermosillo, Sonora
210
map developed by Arias et al (1996) for an ecological planning project (Proyecto de Ordenamiento
Ecologico del Estado de Sonora), livestock could be practiced in about 57.14%, that includes
38.07% of Sonora covered by desert shrubs, grasslands in 13.06%, and about 6.01% of desert
shrubs conditioned on rainfall availability. What seems more interesting is the fact that livestock is
the most important activity in terms of aerial coverage in Sonora.
Economic figures from 1985 to 1994 shows that the economic impact of this activity has been
steadily decreasing from 4.1 to 3.25%. Also, agriculture displaced livestock as the main primary
activity in the state after the green revolution when large areas of the plains were incorporated to
agriculture due to reservoir and irrigation structures construction. Less rural population is involved
in livestock, and although the numbers does not decrease significantly, the percentage of
population and the percentage of participation in the Internal Revenue Product is decreasing, in
part due to the grow of the industry and tertiary sectors (Arias et al, 1996a).
Natural resources mismanagement has been strongly correlated with land degradation processes.
COTECOCA (Technical Commission for the Estimation of Carrying Capacity), the authority for
assessing range management, claims that in 1994, the estimated average range occupation was
10.51 ha/au, while the recommended average carrying capacity for Sonora is 22.2 ha/au
(unpublished data), and as a result, they consider that erosion is increasing. This is why it is
important to know what degradation processes are responsible for land degradation; and if it is so,
at what extent is affecting the land, and where are the areas most affected. It would not only
provide information of the problem but where to apply corrective measures.
This project addresses the question: is there a way to reduce land degradation processes, like
erosion or salinity, to increase the land productivity, which will eventually improve the economic
condition of ranchers?. Sustainable development claims for the reduction of land degradation
processes and increase the land productivity in an anthropocentric fashion; that is, improve man's
socioeconomic conditions. However, it involves natural resource management. Since natural
resource management is made by land owners, programs focused to induce sustainable
development must deal directly with the land owners, especially low income farmers who might be
most affected by land degradation processes and declining land productivity.
What is described here is a natural resource management program in a watershed level in
northwestern Mexico. The main objective is sustainable development, as was above presented, by
increasing land productivity, reduce land deterioration, to improve the land owner's conditions. The
short term goal is the generation of a HMaster Plan" for the Matape wat.~rshed, which could have
been the Hcradle" of livestock in northwestern Mexico and southwestern United States.
MATERIALS AND METHODS
Watershed description. The Matape watershed is a 7,249.87 km 2 drainage area of the Matape
River, a 200 km ephemeral stream that drains into the Gulf of California, or Sea of Cortez, East of
Guaymas. There are two cities, Guaymas and Empalme, both in the coastline, representing the two
municipal heads of the Lower Matape; other communities are La Misa, Ortiz, and San Marcial. In
the upper watershed there are three municipal heads, La Colorada, Matape (Villa Pesqueira) and
Mazatan, representing the largest rural communities, along with Cobachi.
211
Figure 1. Map of the iVIatape watershed in Sonora, Mexico. Large cities are in capital
letters. Small letters are for sierras, reservoirs (P.), and towns.
Resource inventory.
The resource inventory was performed by digitizing map information of soils (INEGI, 1982), land
use and vegetation (INEGI, 1984), at a 1:250,000 scale maps using ERDAS version 7.5 and ILWIS
version 4.0. The topography map was produced using Digital Elevation Models (OEM) available
from INEGI at 1:250,000 scale. DEM's were also used to generate a slope range map for erosion
calculations.
Degradation Processes.
The degradation processes analyzed were salinity and erosion because they are related to
agricultural and/or livestock activities.
The Salinity map was obtained from soil maps (INEGI, 1982), since soil chemical data was included
in terms of electrical conductivity, EC (dS m·1), and Sodium Adsorption Ratio, SAR (%), based on
the US Salinity Laboratory Staff (1954) report. This information was updated using maps from the
National Water Commission (Comision Nacional del Agua, 1992) for the Irrigation District of
Guaymas.
The erosion map was obtained using the Universal Soil Loss Equation as described by Arias et
al (1996b). The equation has six factors: (1) erosivity, obtained from an erosivity map provided by
212
Colegio de Postgraduados (1991), (2) soil erodibility, obtained from soil maps according to the
methodology cited by Colegio de Postgraduados (1991), (3 and 4) slope and length factors,
estimated from Digital Elevation Models converted to slope gradients and equations provided by
Wischmeier and Smith (1994), (5) cover management factor, calculated according to Wischmeier
and Smith (1978) for crop and rangeland, and Dissmeyer and Foster (1980) for forest lands, and
(6) the mechanical practice factor was set to 1.0, because it was not possible to detect areas with
erosion control works at the scale we worked.
RESULTS AND DISCUSSION
Since the watershed is very large (7,2 ~9.87 km 2 ), it was divided into Upper (3,141.85 km 2 )
and Lower Matape (4,108.02 km 2 ) by the Reservoir Punta de Agua (Ignacio Alatorre).
Climate.
Climate is hot and dry. There are 4 meteorological stations in the watershed in an elevation
gradient: Matape (745 m), La Colorada (390m), Punta de Agua (245m), and Empalme (10m).
There is a rainfall gradient from the coast, since total annual rainfall is 7 42 mm for Matape, 350.9
mm for La Colorada, 411.3 mm in Punta de Agua, and 166.4 mm in Empalme, related to the
elevation gradient. Figure 2 shows the monthly rainfall and the marked differences in rainfall along
the watershed for the two main rainy seasons, summer (Jun-Oct), and winter (Dec-Mar). Although
the summer rainfall is larger, a substantial amount is provided in the winter, too.
What is really interesting is the fact that the rainfall regime in the upper part is favorable for
livestock, and sets the basis for a reclamation program, in terms of cattle raising, once the other
factors are present; that is, a germ plasm of native vegetation that can increase the carrying
capacity.
200.0 - r - - - - - - - - - - - - - r l = = : = - r - - - - - - - - - ,
180.0
160.0
'E
14o.o
.§.
120.0
::I
100.0
z
80.0
~
~
-a--Matape
60.0
_ -1:r- _ La Colorada
_. _<>- __ A.mta de Agua
__ x _ _ Errpalrre
C)
...J
::>
<(
::::>
....,
{.)
w
0
TIME(month)
Figure 2. Monthly rainfall in four stations in the Matape Watershed.
213
Temperature.
The temperatures can be considered high and decreasing with elevation. The average monthly
maximum temperatures ranges from 40's in Empalme to 30's in Matape. The average monthly
minimum temperatures ranges from 10 to ·15 °C in Em pal me, while in the upper part the minimum
temperatures ranges from 0 to 15 °C (Figure 3).
~1\fetape
_. _<>- __ La Colorada
0:
~"
F\.mta de Agua
- . x _. 8rpalrre
~1\fetape
_. _<>- . . La Colorada
·" ··h." . F\.mta de Agua
- . x _ . 8rpalrre
Figure 3. Maximum and minimum temperature in the
meteorological stations of the Matape watershed.
Evaporation.
Pan evaporation is very high in La Colorada (2,430.4 mm/yr) and Punta de Agua (2,610. 7
mm/yr), as can be seen from Figure 4. That is very important in terms of planning for the efficient
use of water in the area. For instance, water harvesting techniques need to account for this
disadvantage.
Hydrology.
The main stream starts in Sierra Agua Verde, the highest peak (1680 m), filling La Haciendita
Reservoir, after passing Matape. It travels southwest, passing Cobachi, up to San Jose de Pi mas, where
it turns south. In San Marcial, the stream turns southwest again and fills Punta de Agua reservoir.
Although the river continues in the same direction, most of the water is diverted to irrigation channels
at La Misa. In Ortiz, it is a dry stream, and most of runoff is collected in what is called Bordo de Ortiz,
a water retention structure used to grow forage crops. This structure has its origin on colonial times,
but the technique apparently was also used by native Mexicans in pre-Columbian times. From Ortiz, the
river goes south to Empalme, where it drains in Estero el Rancho. Several other small streams drain
into San Carlos, Guaymas, and along the coast (Figures 1 and 5).
214
400.0
350.0
0
i=
<o:: E
0 E
300.0
250.0
... o- .. La Colorada
200.0
-o-- A.mta de Agua
a.- 150.0
~
w
100.0
50.0
0.0
z
<(
....,
Ill
w
u.
0::
<(
~
0:::
0..
<(
~
~
~
....,
5....,
C)
~
0..
w
(J)
b 6
0
z
(.)
w
0
TIME(months)
Figure 4. Average monthly pan evaporation in the Upper Matape Watershed.
···n(servorr
LiJ'Ha(.Cl.emfp~subwatershed
MAT.AJ'E
.-........
.
La_Hac1ep: . a reservorr
Figure 5. Stream network and location of streams, major reservoirs,
ponds and channels. Four meteorological stations: Matape, La Colorada,
Punta de Agua and Empalme are shown. Punta de Agua is also a gaging station.
215
Runoff.
The only gaging station in the watershed is Punta de Agua, located in San Marcial, and runoff
data is available from Jun. 1957 until Dec. 1969 when it was changed to the new location nearby,
named Punta de Agua II in Jul. 76 - Dec. 78, and Jan. 82 - Dec. 85. It is a staff gage, calibrated
with a flow meter. Annual runoff were 11.99 and 9.01 mm/yr in Punta de Agua I, and Punta de
Agua II, respectively. Figure 6 shows the runoff season, and again, the summer rains are the ones
that contribute the most runoff
7.00
e
g
:I:
1D..
w
c
LL
LL
6.00
5.00.
4.00
3.00
0
2.00
:::::»
1.00
z
0:::
-P.Agual
c::::J P. Agua II
0.00
z
....,
<(
c:o
w
LL
0:::
<(
~
0:::
z
::::>
....,
~
a..
<(
~
..J
6z
"
::::>
....,
::::>
<(
~Average
(.)
w
0
TIME(Month)
Figure 6. Monthly runoff depth (mm) distribution in Punta de Agua I (Jun. 57 -Dec. 69), and
Punta de Agua II (Jul. 76 - Dec. 78, Jan. 82 - Dec. 85). Average is shown as a line.
The highest discharge rate was 636 m3/s. In general, the runoff distribution follows the same
pattern as the rainfall data, since the most intense runoff events happen in the summer (Jun.-Oct.),
as can be see from Figure 7.
700.0
.!!!
C"')
g
600.0
w
500.0
0:::
<(
400.0
g PAgua I
:I:
0
300.0
.P. Agua II
i5
200.0
C)
rn
X:
<(
w
D..
100.0
0.0
z
<(
....,
c:o
w
LL
0:::
<(
~
0:::
a..
<(
~
~
z
::::>
....,
..J
"
::::>
....,
::::>
<(
a..
w
U)
~
(.)
0
>
(.)
z
0
0
w
TIME(Month)
Figure 7. Maximum peak discharge rates (m3/s) at Punta de Agua I (Jun. 57-Dec. 69), and
Punta de Agua II (Jul. 76 - Dec. 78, Jan. 82 - Dec. 85).
216
Sediments.
Sediment concentration is related to the intensity of runoff and most of the sediment
transporting events occur during the summer (Jul.-Sept.), as can be seen in Figure 8. Annual
3
sediment yield are 389,700 m , and 210,600 m3 , for Punta de Agua I and II, respectively, with an
average of 322,200 m3 •
200
180
C")
160
0
:!:.. 140.
c...J 120
w 100
>= 80
1z
w 60
::::E
40
2i 20
w
U)
0,
C")
E
_P.Agual
c::::::J P. A gua II
-+-Average
z
<(
....,
fil
w
u..
0::
0::
~
<(
<(
a..
~
~
z
:::::>
....,
...J
:::::>
....,
(!)
:::::>
<(
a..
w
(/)
1-
(.)
0
>
(.)
z
0
0
w
TIME(month)
Figure 8. Monthly sediment volumes (thousands of m3 ) at Punta de Agua I (1961-1969) and
Punta de Agua II (1982-1985), as well as the average for the two stations.
Reservoirs.
In the watershed there are 4 major reservoirs: Punta de Agua with a capacity of27.9 hm 3 occupying
an area of 426 ha, which irrigates 25,467 ha in the Irrigation District 84 Valle de Guaymas. A unique
feature is "Bordo de Ortiz", which is a runoff detention structure used to grow forages and is considered
the largest water harvesting structure in the state with a capacity of 2. 75 hm 3 , in an area of 269 ha.
La Haciendita has a capacity of 3.4 hm 3 , an area of 125 ha, and Homos with a capacity of 1.0 hm 3 ,
an area of 100 ha, both of them to grow forage crops in small areas. Figure 5 shows the reservoirs.
There are many small ponds to supply water for cattle, but they are difficult to identify in the map
because of the size.
Soils.
Most soils of the region are limited by arid conditions (Xerosols and Yermosols), others are very
shallow soils (Regosol and Leptosol, formerly Litosol). The soils that have possibilities for agriculture are
Phaeozems (3.25%) and Vertisols (13.28%). Those soils are occupied by agriculture or intensive
ranching. The desert soils, once water is available either by pumping or surface irrigation, can be used
for either agriculture or livestock.
217
•
......,
'..r'"O
•
•
•
•
D
D
CAHBISOL
REHDZIHA
FEOZEH
LITOSOL
FLUVISOL
LUVISOL
REGOSOL
VERTISOL
PLAHOSOL
~EROSOL
VERHOSOL
SOLOHCHAH
Figure 9. Soil map of the Matape watershed according to FAO classification
SOILS {FAO CLASSIFICATION}
AREA {HA}
175282
174063
145737
96212
29559
28568
27095
24481
13560
4033
2404
3461
Regosol
Leptosol
Xerosol
Vertisol
Planosol
Fluvisol
Yermosol
Phaeozem
Solonchak
Luvisol
Rendzina
Cambisol
218
{%}
24.20
24.03
20.12
13.28
4.08
3.94
3.74
3.38
1.87
0.56
0.33
0.48
Land use and vegetation.
Most of the vegetation belongs to desert life forms, shrubs and mesquite lands are the most
important vegetation classes, in terms of area (about 83%). Introduced species are represented by
irrigated agriculture in the alluvial fans by the coast, and improved grasslands, mainly with buffel
grass, and they both add to 9. 77%. Transition vegetation are represented by Low jungle, from arid
zone to the tropical zone, as well as oak vegetation (forest) to the Sierra Madre Occidental
(temperate zone). It is important to mention that most of the dryland agriculture is practiced in the
river stream bed for forages (Figure 10).
Land degradation processes and degradation phenomena, erosion and salinity, were mapped
using mathematical models, digitized maps, and Geographic Information Systems. Salinity. Most of
the irrigated croplands in the lower Matape watershed have salinity problems as well as the coastal
areas (Figure 11). Saline-sadie soils are the most abundant (8.10%), in terms of salinity problems,
followed by saline soils (4.08%), and strongly saline-sadie soils (3.04%). The irrigated agriculture
has been practiced pumping groundwater and, as a result, most of the salinity problems in croplands
are related to saline intrusion. A reclamation program needs to know the type of problem and the
area to reclaim. The map (Figure 11) helps in establishing a salinity reclamation program by
overlapping the cropland map and the type of salinity problem.
Erosion.
GIS studies showed that erosion is a very important degradation process in the Matape
watershed (Arias et al, 1996b) by using the Universal Soil Loss Equation to estimate average annual
soil losses. The average annual soil losses for the entire watershed are 11.76 Mg/ha/yr. The upper
Matape watershed, with steeper slopes and livestock as the main activity, have average annual soil
losses of 16.85 Mg/ha/yr, and the lower watershed, with less steep lands and irrigated agriculture
and some rangeland are the main economic activities, have average annual soil losses of 7.87
Mg/ha/yr. Field observations and rainfall simulation studies carried along with the USDA-ARS
allowed us to check two sites and the average soil losses were the same, 4 Mg/ha/yr, as those
estimated with the USLE (Lane, Nichols, and Arias, 1994) .Tolerable soil losses vary depending on
the parent material, soil class and depth, as some of the most important factors; however, any rate
larger than 8 Mglha/yr is above the natural soil-forming rate, an equilibrium condition.
About 88% of the land has soil losses below 8 Mg/ha/yr; it means that the problem are the
hillslope areas. Therefore, we can say that the erosion is a major problem in the upper Matape
watershed lands, since the soil losses are higher than the permissible values.
219
-
SHRUB
HESQUITAL
IRRIGATED AGRICULTURE
l1iii?'id GRASSLAHDS
-LOW JUHGLE
DRVLAHD AGRICULTURE
iB
Ill
c=J
-
fiiJ
Ill
-
FOREST
HALOPHVTES
ABAHDOHED IRRIGATED AGRICULTURE
RIPARIAH
DUHES
HAHGROVE
Figure 10. Land use and vegetation of the Matape watershed.
LAND USENEGETATION
AREA (ha)
413548
198987
36191
35057
18659
6422
5814
5659
3828
502
163
267
Shrub
Mezquital
Irrigated agriculture
Grasslands
Low jungle
Dryland agriculture
Halophytes
Forest
Abandoned irrigated agriculture
Riparian
Mangrove
Dunes
220
PERCENT(%)
57.03
2744
499
4.83
2.57
0.89
0.80
0.78
0.53
0.07
0.02
0.04
C1S1
!i79211
•
C2S1
.ClS1
•
C1S2
2~!i9
•
CJ
C2S2
UClS2
.C1Sl
749£.
!iO!i!i
!ill:.97
22091
1£.9]
.C2Sl
.ClSJ
0
20£.2£.
Figure 11. Salinity map of the Matape Watershed.
The map was obtained from INEGI soil maps.
CLASS
KEY
EC
(dS m·1 )
SAR (%)
Normal
Saline
Strongly saline
Sodie
Saline-sadie
Strongly saline-sadie
Strongly sodie
Saline- Strongly sodie
Strongly saline- Strongly sodie
C1S1
C2S1
C3S1
C1S2
C2S2
C3S2
C1S3
C2S3
C3S3
<4
4-16
>16
<4
4-16
>16
<4
4-16
>16
< 15
< 15
< 15
15-40
15-40
15-40
>40
>40
>40
221
Area
(ha)
578922
29559
7496
5055
58710
22046
1693
0
21495
PERCENTAGE
(%)
79.85
4.08
1.03
0.70
8.10
3.04
0.23
0.00
2.96
CONCLUSIONS
The climatic conditions of the watershed are not very promising for livestock, especially in the
lower part because of high temperature, high evaporation rate, and low rainfall regime. The upper
watershed has better climatic conditions for cattle raising. Since the rainfall amount in the
watershed varies, runoff and/or groundwater represent possibilities for economic activities in the
area. Runoff is widely used in the lower Matape watershed by water retention structures, but in the
upper watershed, with better rainfall regime, programs of water conservation are needed. The two
reservoirs in the area can be used more efficiently providing infrastructure to irrigate larger areas or
supply water to other users. Even though there are not many wells in the upper Matape, it is
possible to pump groundwater, especially in the area of Cobachi-San Jose de Pi mas; however, a
more detailed study is required in order to avoid problems like that in the coastal areas, where
seawater intrusion has affected large areas that used to be irrigated.
Although there are not large areas with good soils, it is very important to consider those areas as
a priority for agricultural o livestock activities since the natural fertility of those soils can have a more
rapid impact in the region. It is also important to know that vertisols, although difficult to work, have
a good potential for crop production.
222
•
•
•
0.1- 1
1-?,
2-4
•
4a 16326412a256 -
fZ2]
•
•
•
•
•
a
16
32
64
12a
256
512
Figure 12. Actual erosion map of the Matape watershed.
SOIL LOSS RANGE
(Mg/ha/yr)
0.1-1.0
1.0- 2.0
2.0- 4.0
4.0- 8.0
8.0- 16.0
16.0-32.0
32.0-64.0
64.0- 128.0
128.0 - 256.0
256.0 - 512.0
UPPER MATAPE
(%)
AREA (ha)
4170
20991
52902
105790
62015
28869
23122
13558
2407
408
314232
LOWER MATAPE
WATERSHED
(%)
AREA (ha)
AREA (ha)
(%)
7.77
60482
0.58
56312
8.35
11.05
2.90
80045
101036
13.95
126641
17.48
179543
24.78
7.30
23.74
9.14
171974
14.60
66184
4.42
8.56
32038
94053
12.98
7.68
3.99
26794
3.70
55663
3.19
18311
2.53
41433
5.72
17188
2.37
1.87
0.50
3630
2644
0.33
0.03
0.36
237
0.06
4
0.00
412
0.06
56.62
724428
100.00
43.38
410196
223
Most of the vegetation in the area is considered as desert vegetation, shrubs and other species;
however, there are still areas with important biological value. Sierra de Mazatan has been proposed
as a state reserve, also in Sierra El Carrizo we have observed native grasses not present in the
lowlands. It is very important to have a more detailed vegetation study to provide other alternatives
in terms of natural resource management in the area.
Salinity was clearly located in the lower watershed, different levels of salinity are present, some
of them are signs of the impact of human activities, but others are due to natural conditions. In the
vegetation map, 3828 ha are shown as abandoned due to salinity. It is also convenient to analyze
the risk of reclamation programs for salinity.
Erosion is a major problem in the upper watershed in general. That is due to steeper slopes
(mainly) and low vegetation cover. Historic references, and climate information, could lead us to
think that grasslands have deteriorated, changing to desert scrubs, and a program to restore
environmental conditions and reduce land degradation is a must for the economic development of
this region.
REFERENCES
Arias, Hector M., Maria L. Fernandez, Gonzalo Luna, and Evangelina Diaz. 1996. Erosion Actual y
Potencial en Ia Cuenca del Rio Matape. Paper presented at the "Segundo Simposio
lnternacional de Manejo de Cuencas Hidrograficas". To be published by the University of
Arizona. Tucson, AZ. Arias, Hector M.; Luis A. Bojorquez, Pablo Wong, Christopher Watts,
Guillermo Soberon, Eric Mellink, Ivan Parra, David Peria. 1996. Proyecto de Ordenamiento
Ecologico del Territorio. Estado de Sonora. Proyecto Ejecutivo. IMADES. Hermosillo, Sonora.
33 pp (In preparation).
Arias, Hector M., C. Watts, R. Acosta, D. Peria, L.J. Lane, J.R. Simanton, and M.H. Nichols. 1996.
Water resources inventory for the Upper Matape River, Sonora, Mexico. Submitted to J. Soil and
Water Conservation.
Atondo, Ana Maria, Sergio Ortega N., Patricia Escandon, Martha Ortega S., Edgardo Lopez M.,
Ignacio del Rio, Juan D. Vidargas del M. 1985. Historia General de Sonora. II. De Ia Conquista
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