 |
| Titel |
Quantification of the effect of terrace maintenance on soil erosion: two
seasons of monitoring experiments in Cyprus |
| VerfasserIn |
Corrado Camera, Hakan Djuma, Christos Zoumides, Marinos Eliades, Katerina Charalambous, Adriana Bruggeman |
| Konferenz |
EGU General Assembly 2017
|
| Medientyp |
Artikel
|
| Sprache |
en
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250143659
|
| Publikation (Nr.) |
 EGU/EGU2017-7404.pdf |
|
|
|
|
|
| Zusammenfassung |
| In the Mediterranean region, rural communities in topographically challenging sites have
converted large areas into dry-stone terraces, as the only way to develop sustainable
agriculture. Terraces allow softening the steep mountainous slopes, favoring water infiltration
and reducing water runoff and soil erosion. However, population decrease over the past 30
years has led to a lack of maintenance of the terraces and the onset of a process of land
degradation. The objective of this study is the quantification of the effect of terrace
maintenance on soil erosion. We selected two terraces – A and B, 11 and 14 m long,
respectively - for monitoring purposes. They are located in a small catchment (10,000
m2) in the Troodos Mountains of Cyprus, at an elevation of 1,300 m a.s.l., and
cultivated with vineyards, which is the main agricultural land use of the region.
We monitored soil erosion by means of sediment traps, which are installed along
1-m long sections of terrace. We monitored four sections on terrace A and seven
on terrace B. During the first monitoring season (winter 2015/16), on terrace A
the traps caught sediment of two collapsed and two standing sections of dry-stone
wall. The catchment areas of one set of traps (degraded and non-degraded) were
closed by a 1x4-m2 plot, to relate erosion rates to a known draining area. On terrace
B the traps were all open and caught four collapsed and three standing sections.
Also, we installed a weather station (5-minute rainfall, temperature, and relative
humidity) and 15 soil moisture sensors, to relate soil erosion processes with climate
and (sub)surface hydrology. From the open traps, we observed that soil loss is on
average 8 times higher from degraded terrace sections than from standing, well
maintained sections, which in our case study corresponds to an 87% reduction
of soil loss due to terrace maintenance. If we compare data from the two closed
plots, we obtain a much higher soil loss ratio (degraded/standing) of 56, which
corresponds to a soil loss reduction of 98%. From the closed plots, we derived
an erosion rate of 2.8 t ha−1 y−1 for degraded terraces and 0.05 t ha−1 y−1 for
well-maintained terraces. Also, soil moisture monitoring confirmed that standing terraces
favor surface water infiltration. For the second season (winter 2016/17), given the
differences in results between open and closed traps and therefore the difficulty in
consistently upscaling the results, we modified the monitoring design. The 11 traps
were kept, all open, but the comparison between maintained and degraded areas is
carried out on a sub-catchment basis, rather than on a section basis. We restored the
whole sub-catchment of terrace A (≈480-m2) to be considered the maintained
treatment of our experiment and kept the sub-catchment of terrace B (≈600-m2)
in degraded conditions. To obtain the sub-catchment erosion rate, the sediment
collected in the traps is averaged on running meter of wall and integrated on the wall
length.
This research is supported by the European Union’s FP7 RECARE Project (GA 603498). |
|
|
|
|
|
|