SESolid EarthSESolid Earth1869-9529Copernicus PublicationsGöttingen, Germany10.5194/se-7-167-2016Integrating a mini catchment with mulching for soil water management in a sloping jujube orchard on the semiarid Loess Plateau of ChinaLiH. C.GaoX. D.ZhaoX. N.xiningz@aliyun.comhttps://orcid.org/0000-0002-4954-8830WuP. T.LiL. S.LingQ.SunW. H.College of Water Resources and Architectural Engineering, Northwest A & F University, Yangling, ChinaInstitute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, ChinaThese authors contributed equally to this work.X. N. Zhao (xiningz@aliyun.com)1February20167116717526October201511November20157January201613January2016This work is licensed under a Creative Commons Attribution 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by/3.0/This article is available from https://se.copernicus.org/articles/7/167/2016/se-7-167-2016.htmlThe full text article is available as a PDF file from https://se.copernicus.org/articles/7/167/2016/se-7-167-2016.pdf
Conserving more soil water is of great importance to the
sustainability of arid and semiarid orchards. Here we integrated fish-scale
pits, semicircular mini-catchments for hill slope runoff collection, with
mulches to test their effects on soil water storage in a 12-year-old dryland
jujube orchard on the Loess Plateau of China, by using soil water
measurements from April 2013 to November 2014. This experiment included four
treatments: fish-scale pits with branch mulching (FB), fish-scale pits with
straw mulching (FS), fish-scale pits without mulching (F), and bare land
treatment (CK). Soil water was measured using the TRIME®-IPH time-domain reflectometer (TDR) tool in
20 cm intervals down to a depth of 180 cm, and was measured once every 2 weeks in
the 2013 and 2014 growing seasons. The results showed that fish-scale pits
with mulching were better in soil water conservation. Average soil water
storage (SWS, for short) of FB at soil layer depths of 0–180 cm increased by
14.23 % (2013) and 21.81 % (2014), respectively, compared to CK, but
only increased by 4.82 % (2013) and 5.34 % (2014), respectively, for the
F treatment. The degree of soil water compensation, WS, was employed
here to represent to what extent soil water was recharged from precipitation at
the end of the rainy season relative to that at the beginning of the rainy season. A
positive (negative) WS larger (lower) soil water content at the
end of rainy season than at the beginning. For the treatment of FB, the
values of WS over the entire soil profile were greater than 0; for the
treatment of F, negative values of WS were observed in depths of 60–100 cm
in both years. However, the bare land treatment showed negative values in
depths of 40–180 cm. This indicated that integrating fish-scale pits with mulching
could significantly increase soil water storage by increasing infiltration
and decreasing evaporation, and it showed greater soil water storage and degree
of soil water compensation compared to fish-scale pits alone. Since the
branches used for mulching here were trimmed jujube branches, the cost of
mulching materials was largely reduced. Therefore, integration of fish-scale
pits with branch mulching is recommended in orchards for soil water
conservation on the Loess Plateau and potentially for other regions.
Introduction
The hilly region of the Loess Plateau of China is a typical semiarid region.
The annual precipitation of the region ranges from 200 to 750 mm, with
70 % occurring between July and September, often in the form of heavy
rainstorms (Zhao et al., 2013). As a result, drought and serious soil
erosion frequently occur in this region (Zhao et al., 2014). Soil water
content plays a vital part in the land surface system as it controls
hydrological, erosional, and biogeochemical cycles, and supports services to societies (Brevik et al., 2015; Berendse et al., 2015; Keesstra et al.,
2012). Vegetation could protect the soil surface from drop impact,
increasing resistance to concentrated flow erosion (Cerdà, 1998;
Keesstra et al., 2009), and decreasing runoff discharge during rainstorms
(Seutloali and Beckedahl, 2015; Q. Y. Li et al., 2014). Vegetation cover on the
Loess Plateau was significantly improved after the implementation of the “Grain
for Green” project, a large-scale ecological project by converting hillslope
farmland to forest (including economic plantations such as orchards) or
grassland (Liu et al., 2014; Yu et al., 2014; Zhao et al., 2015). However,
regional-scale vegetation restoration in a short time increases soil
water consumption quickly and this further deepens soil water deficit
in this region (Gao et al., 2014).
Water harvesting systems for runoff water collection and storage represent
an attractive solution for resolving water scarcity in various parts of the
world (X. H. Li et al., 2014; Mwango et al., 2015; Ola et al., 2015). In many
regions of China, semicircular mini-catchments, known as “fish-scale
pits”, which are built on slopes in an alternating pattern similar to the
arrangement of the scales of a fish, can effectively reduce runoff and soil
erosion and improve land productivity (Mekonnen et al., 2015a, b). Fu et
al. (2010) found that the fish-scale pit could effectively reduce surface runoff
and sediment transport during heavy rainstorms and thus increase soil water
infiltration. However, Li et al. (2011) showed that the average soil water
content inside fish-scale pits was below the levels of the external slopes
during July and August, because the fish-scale pits increase evaporation
as a result of the enlarged partial soil water and contact area between soil and
air (Mekonnen et al., 2015a).
A lot of field and laboratory studies have shown that organic mulching can
increase soil water storage by reducing storm runoff (Moreno-Ramón et
al., 2014; Sadeghi et al., 2015), increasing infiltration (Montenegro et
al., 2013), and decreasing evaporation (McIntyre et al., 2000; Sas-Paszt et
al., 2014). Chakraborty et al. (2010) found that organic mulches had better
soil water status and improved plant canopy in terms of biomass, root
growth, leaf area index, and grain yield, which subsequently resulted in
higher water and nitrogen uptake and their use efficiencies. Suman and Raina (2014)
investigated the effect of plastic mulches on the soil water of apple
orchards at Krishi Vigyan Kendra, Himachal Pradesh, India. They found that
the mulches conserve 2–4 % higher soil water content over unmulched
conditions, especially in surface soil layers. On the tableland (relatively flat
surface) orchards in the Loess Plateau, mulching has been widely used for
conserving soil water content. Fan et al. (2014) found that straw mulching
and broken stone mulching increased soil water content and water use
efficiency in alfalfa in the northern Loess Plateau. Liu et al. (2013) found
that straw mulching notably increased the soil water content by decreasing
the soil bulk density and increased the soil porosity of a nonirrigated
apple orchard in the Loess Plateau, China. Gao et al. (2010) found that
straw mulching enhanced soil porosity and increased the soil-water-holding
capacity within a 60 cm soil layer after 3 years mulching in an apple orchard
on the Weibei Plateau.
However, the studies with respect to mulching in the above citations were
all implemented at sites with flat surfaces or gentle slopes. For sites with
an apparent slope, mulch materials are not stable and prone to being taken away
by gravity or external forces. Since fish-scale pits are built on hill
slopes and have low and flat surfaces inside, here we try to integrate
fish-scale pits with mulches, aiming to test their effects on soil water
storage in sloping jujube orchards in the semiarid region of the Loess Plateau.
Materials and methodsStudy site
The field study was conducted from 10 October 2012 through 5 November 2014
at the Mizhi experimental station of Northwest A & F University. The
station is located at 38∘11′ N, 109∘28′ E
in Mizhi county, in the city of Yulin of Shaanxi province, China. On the basis of
data from 1966–2006, this site has a semiarid continental climate with a
mean annual precipitation of 451 mm, a temperature of 8.5∘,
solar radiation of 161.46 W m-2, frost-free periods
of 160 days, and 2720 h of sunshine on average each year (Bai and Wang, 2011; Zhang
et al., 2010). The soil is primarily composed of loess, with a texture of fine
silt and silt loam. A summary of information on soil properties in depths of 0–180 cm is
shown in Table 1.
Jujube trees were planted in 2001 on a 20∘ southward-facing slope and
cultivated under rainfed conditions with row-by-stand spacing of 3 m by 2 m,
respectively. Every year, 300 kg N ha-1,
70 kg P2O5 ha-1, and 150 kg K2O ha-1 of fertilizer were applied on the cultivated
jujube trees. Pest and weed control measures were also taken every year. The
trees were pruned every year, not only as a crop water uptake management
measure, but also to maintain a 2 m canopy height and a uniform canopy shape
of a spherosome.
Treatments
Four different treatments were established in this study including
fish-scale pits with branch mulching (FB), fish-scale pits with maize straw
mulching (FS), fish-scale pits without mulching (F), and bare land treatment (CK).
Each treatment had three replicates. The fish-scale pit had a volume
of 100 cm (length) × 80 cm (width) × 30 cm (depth). A
photo showing this system is presented in Fig. 1. Trimmed jujube branches
and maize straws were utilized for mulching with lengths of 5–10 cm and a
mulching thickness of 15 cm.
A photo of a fish-scale pit.
Soil water measurements
A portable time-domain reflectometer (TDR) system, TRIME®-PICO IPH/T3 (IMKO,
Ettlingen, Germany), was used to monitor soil water in this jujube orchard.
This TDR system consists of a TRIME®-IPH probe, a TRIME® Data Pilot
data logger, and fiberglass access tubes (Φ= 40 mm). A 180 cm deep pit was
excavated 0.5 m from the access tubes to collect undisturbed soil samples
from the corresponding depths in order to obtain measurements of the dry
soil bulk density and gravimetrical soil moisture content (θ).
Values of θ were then transformed to volumetric moisture contents,
and a calibration curve was generated by plotting the measured TDR-derived
moisture values (θTDR, cm3 cm-3) against the volumetric
moisture contents (θ, cm3 cm-3), and fitting a regression
equation (Eq. 1, R2= 0.915, RMSE = 3.77 %).
θ=0.926×θTDR-3.854
There were 12 sampling points in total. Soil moisture was sampled at these
points at depths of 0–180 cm at 20 cm intervals during two periods: from
5 June to 20 September 2013 and from 10 June to 30 September 2014. During
the two periods, soil moisture was sampled approximately weekly and 1 h after rainfall events. During the entire sampling periods there were
24 sampling occasions. On each sampling occasion, soil moisture was sampled
within 4 min at each sampling point and all the soil moisture measurements
were taken within 2 h. During such short times, the temporal variation of
soil moisture was expected to be negligible. According to existing research
results (Gao et al., 2011; Ma et al., 2012, 2013) concerning root systems of
jujube forests, soil layer depths of 0–20 cm were considered to be the surface
layers, 20–100 cm the main root system layers, and 100–180 cm the deep layers.
Indexes
We hypothesized that precipitation and evapotranspiration are the main
factors controlling root-zone soil moisture dynamics at the study site
because the groundwater table in the Loess Plateau is usually deeper than
50 m (Gao et al., 2011). Soil water changes are mainly related to precipitation
and evapotranspiration. We used the following two indexes to represent the
degree of soil water storage (SWS) deficit (WD, Eq. 2) and the degree of water compensated by
precipitation (WS, Eq. 4) (Zhang et al., 2009):
WD=DFc×100%D=Fc-Wc,
where WD (%) refers to the degree of SWS deficit, D (mm) refers
to the SWS deficit, Fc (mm) is the field capacity, and Wc (mm) is the measured SWS.
WD is used to represent the degree of SWS deficit relative to field
capacity. If WD= 0, it means that the soil water storage
deficit has been completely recovered; if WD> 0, it means that a soil
water-storage deficit existed, with higher values indicating severer SWS deficits.
WS=ΔWDac×100%ΔW=We-WccDac=Fc-Wcc,
where ΔW (mm) represents increased SWS at the end of the rainy
season, We (mm) represents SWS at the end of the rainy season
(25 September 2013 and 25 October 2014), Wcc (mm) represents SWS at the
beginning of the rainy season (5 June 2013 and 2014), and Dac (mm)
represents the SWS deficit at the beginning of the rainy season.
Temporal changes of (a) temperature and precipitation, (b) 0–20 cm
soil water storage, (c) 20–100 cm soil water storage, and (d) 100–180 cm soil
water storage for fish-scale pits with branch mulching (FB), fish-scale pits
with straw mulching (FS), fish-scale pits without mulching (F), and bare land
treatment (CK). Error bars represent ±1 SD (1 standard deviation).
Deficit degree of soil water storage under fish-scale pits with branch
mulching (FB), fish-scale pits with straw mulching (FS), fish-scale pits
without mulching (F), and bare land treatment (CK).
TreatmentsDepthDegree of soil water storage deficit (%) (cm)2013 2014 JuneJulyAugustSeptemberJuneJulyAugustSeptemberOctoberFB0–2041.778.7212.1342.2539.6620.2028.0410.909.9820–10043.8625.279.5630.5240.2117.5627.9514.7015.83100–18047.3146.8438.8841.8634.3742.6641.7843.2741.83FS0–2046.0611.6515.2351.5542.1820.5232.969.1010.3820–10045.8529.0014.3543.1844.9818.9029.5017.4018.37100–18048.6647.5741.2044.7042.9945.9246.5544.5448.17F0–2051.3421.7228.1954.7348.7829.0642.6828.5724.7520–10047.1534.0620.7542.9140.0130.4841.9227.9127.13100–18049.2748.3443.4544.7136.4545.4846.2745.8647.18CK0–2052.6721.0336.2661.8346.1336.5146.1141.7238.6120–10048.3232.5133.8150.8343.1941.1039.0730.1933.05100–18046.5847.7445.8047.7942.9449.4248.0146.3146.94
Vertical changes of soil moisture before (BF) and after (AP)
typical precipitation in June (a–d), July (e–h), and
August (i–l) under fish-scale pits with branch mulching (FB), fish-scale pits with
straw mulching (FS), fish-scale pits without mulching (F), and bare land treatment (CK).
WS is used to reflect to what extent SWS is recharged at the end of the rainy
season relative to SWS at the beginning of the rainy season. If
WS≤ 0, it means that the SWS deficit increases; if WS> 0,
it means the SWS deficit has been alleviated; if WS= 100 %, it
indicates that the SWS deficit has been completely compensated for.
Statistical methods
Statistical analysis was conducted using Microsoft Excel 2010 (Microsoft,
Redmond, USA) and SPSS16.0 (SPSS, Chicago, USA) software. Differences
(α= 0.05) among the various treatments were analyzed using two
methods: one-way analysis of variance and multiple comparison analysis least significant
difference.
Results and analysisTemporal dynamics of soil water storage
The characteristics of rainfall, temperature, and SWS of 2013 and 2014 in
different soil layers with time are shown in Fig. 2. The rainfall mainly
occurred from July to September, which accounted for 66.7 % (345.6 mm) and
65.9 % (289 mm) of annual rainfall in 2013 and 2014, respectively. Water
in the soil surface layers was greatly influenced by rainfall events and
evapotranspiration, which increased clearly following apparent rainfall
events. The SWS in depths of 20–100 cm behaved similarly in time with the surface
SWS. The FB and FS treatment showed consistently higher SWS than the F and
CK in the 0–20 and 20–100 cm soil layers, particularly following rainstorms. The SWS
in the deep soil layers was weakly affected by precipitation. Overall, for
the whole study period in 2013 the average SWS in depths of 0–180 cm for the FB,
FS, and F treatments increased by 14.23, 9.35, and 4.82 %, respectively,
compared with CK; and in 2014, the values were 21.81, 17.18, and 5.34 %, respectively.
Vertical changes of soil water following typical rainfall events
One typical rainfall event was chosen in each month of June, July, and August in 2013 to
analyze the effect of a single rainfall event on the vertical distribution of soil
water content. The precipitation in June, July, and August was 41.2, 64.2,
and 29.6 mm, respectively. Soil water was measured before rainfall and this
was done again 3 (June and July) or 7 (August) days later after rainfall ceased.
From Fig. 3, it can be observed that soil water increased dramatically in
the 0–20 cm layer for different treatments following the 41.2 mm rainfall event
(19–20 June 2013). However, soil water changed negligible
after the rainfall beneath the 40 cm, indicating only shallow soil water was
recharged. A heavy rainstorm of 64.2 mm occurred from 6 to 11 July 2013.
Before the rainfall event, soil water content was relatively low
(< 13 %) over the entire profiles. Three days after rainfall, the
soil water content for the FB, FS, and F treatments significantly increased
at 0–60 m, but for the CK, an apparent increase in soil water content was only
observed in depths of 0–40 cm. It showed that fish-scale pits promoted soil water
infiltration during heavy rainstorms. Soil water content for the majority of
soil layers in depths of 0–180 cm decreased compared with before the rainfall
event. This was probably caused by strong water consumption of jujube trees
during this inter-rainstorm period.
Soil water deficit and recoverySoil water deficit
Here we averaged SWS each month to calculate monthly SWS deficit. From Table 2,
it can be seen that SWS deficit existed for all treatments from June to
September at 2013 and from June to October at 2014. In June for both years,
SWS deficits in depths of 0–180 cm were relatively severe for all treatments. In
the following months, SWS deficits in the 0–20 and 20–100 cm layers decreased
apparently with the increase of rainfall events (Fig. 2). This suggests
that soil water supply from precipitation could not only meet the large
water demand of jujube trees but also provide excess water to recharge
soils. Note that in September of 2013, the SWS deficit in the top 100 cm
increased sharply because of a significant decrease in precipitation. However,
a high SWS deficit in depths of 100–180 cm persisted over the wet season,
indicating that little water recharged into this depth.
Relationship between compensation degree of soil water storage
deficit (WS) and soil depth at 2013 (a) and 2014 (b) under fish-scale
pits with branch mulching (FB), fish-scale pits with straw mulching (FS),
fish-scale pits without mulching (F), and bare land treatment (CK).
Soil water recovery
The changes of the degree of SWS compensation (WS) with depth after the rainy
season are illustrated in Fig. 4. From the figure, it can be
observed that there were apparent differences of the degrees of SWS
compensation for different treatments after the rainy season. For the
treatment of FB, the values of WS over the entire soil profile were greater
than 0; for the treatment of F, negative values of WS were observed in the
60–100 cm soil depths in both years. However, the CK treatment showed negative values in
depths of 40–180 cm. This indicated that the FB treatment exerted positive
compensative effects on soil water within the 0–180 cm depth. For the FB,
FS, and F treatments, positive compensative effects existed in depths of 100–160 cm,
demonstrating that fish-scale pits played active roles in water
compensation in deep soil layers. The pits artificially improved the
roughness of the slopes, leading to enhanced rainfall infiltration. In both
years, the WS of the 20–100 cm soil layer with the FB treatment was
significantly higher than for the F and CK. For the F treatment in the
0–100 cm layer, the compensation degree fluctuated around 0, demonstrating that the
fish-scale pits without mulching exerted basically no compensative effects
on depths of 0–100 cm. However, in depths of 100–160 cm, a compensative effect
is observed on the soil water for the F treatment.
Discussions
The annual precipitation of the hilly region of the Loess Plateau is only
250–550 mm, while annual field evapotranspiration is 750–950 mm, and the
groundwater table is usually deeper than 50 m (Gao et al., 2011). Therefore
perennial jujubes are often under the stress of drought. The fish-scale pits
can strengthen the roughness of slopes, enhance rainfall infiltrations, and
ensure water supply for plants in the pits during the rainy season (Fu et
al., 2010). Our results indicated that the fish-scale pits improved the soil
water by 5.08 % compared with control. The value was much lower compared
with Wang et al. (2015) who found that soil water content increased by 14.06 %
inside fish-scale pits for 1-year-old Robinia Pseudoacacia in the Loess Plateau
of China. A possible explanation is that the 12-year-old jujube trees in
our study used more soil water.
The results of our study indicated that integrating fish-scale pits with
mulching increased SWS (Fig. 2) and decreased SWS (Table 2) deficit during
both rainstorms and drying periods compared to the treatment of fish-scale
pits alone. On the one hand, during the dry periods between rainstorms, fish-scale pits
increase soil evaporation because of the larger contact area of soil and
air; during the rainstorms, the physical crust which is caused by runoff also
reduces the treatment of fish-scale pitsthe infiltration (Previati et al., 2010). On the other hand,
mulching could effectively reduce the formation of soil physical crust by
filtering soil particles during rainstorms, improved soil water-stable
aggregates, and increased soil-water-holding capacity (Lin and Chen, 2015).
Previous studies have also suggested that organic mulching promotes the
activity of soil microorganisms and the formation of a soil aggregate
structure, thereby improving the soil structure and increasing the soil
water content (Siczek and Lipiec, 2011). Meanwhile, we found that
integrating fish-scale pits and mulching increased soil water consumption
(Fig. 2). In general, organic mulching provides better soil water status
and improves plant canopy in terms of biomass, root growth, leaf area index,
and grain yield (Ram et al., 2013). These together would subsequently result
in a higher water and nutrient uptake. However, mulching can largely reduce
soil evaporation (Liu et al., 2013; Sadeghi et al., 2015). Since soil water
consumption is generally equal to the sum of soil evaporation and plant
canopy transpiration (Chakraborty et al., 2010), it means that the mulching
would increase the ratio of transpiration in the total of soil water use.
In this study, jujube branches and maize straw, two kinds of easily
accessible local materials, were selected as mulching materials for the
fish-scale pits. The results showed that jujube branches exerted better
mulching effects than maize straw, possibly because the straw had relatively
strong water-holding capacity. During the rainfall stages, the straw
intercepted and preserved the rainfall water, and after the rainfall stage,
the intercepted and preserved water dissipated rapidly as vapor when the
exposed areas of the straw to air were relatively high. Similar results have
been reported by several studies in the past (Lin and Chen, 2015; Li et al.,
2013). In addition, maize straw is more and more difficult to obtain
following the decrease of cultivated land. The jujube branches were mainly
obtained from the annually trimmed branches. The application of trimmed
branches as mulching materials decreased the cost of the processing and
transportation of material. The use of trimmed branches also helped with the
double objectives of rainfall interception and storage, and soil water
preservation, providing both an economic and ecological benefit in jujube
orchards of loess hilly regions. However, the mechanism of the effects of
integration of fish-scale pits and mulching on soil water storage in sloping
jujube orchards is still not fully understood. Furthermore, how the
integration of fish-scale pits and mulching affects evapotranspiration and
its partitioning of jujube orchards, as well as jujube yield, is still under
investigation. Future studies should pay more attention to these questions
to provide better guidance for the sustainable development of jujube
orchards on the Loess Plateau.
Conclusions
During the growth periods of jujube, all the combinations of fish-scale pits
with mulching measures significantly improved SWS in surface layers (depths
of 0–20 cm) and main root system layers (depths of 20–100 cm). Among these
combinations, the fish-scale pits with branch mulching treatment (FB)
exhibited the most significant effects, followed by the treatment of fish-scale
pits with straw mulching (FS). For dryland jujube orchards in loess hilly
regions, the application of trimmed branches as mulching materials not only
reduced the volume of materials, transportation costs, and difficulties in
construction, but also achieved the goals of increasing rainfall
interception and storage, as well as improving soil moisture preservation
and water storage.
Acknowledgements
This work was jointly supported by the National Natural Science Foundation
of China (41401315, 41571506, 51579212), the “111” Project from the
Ministry of Education (no. B12007), West Light Foundation of the Chinese
Academy of Sciences, and the Natural Science Foundation of Shaanxi Province
of China (2014JQ5179).
Edited by: A. Cerdà
References
Bai, Y. R. and Wang, Y. K.: Spatial variability of soil chemical properties
in a jujube slope on the loess plateau of china, Soil Sci., 176, 550–558, 2011.
Berendse, F., van Ruijven, J., Jongejans, E., and Keesstra, S.: Loss of
plant species diversity reduces soil erosion resistance, Ecosystems, 18, 881–888, 2015.Brevik, E. C., Cerdà, A., Mataix-Solera, J., Pereg, L., Quinton, J. N., Six,
J., and Van Oost, K.: The interdisciplinary nature of SOIL, SOIL, 1, 117–129,
10.5194/soil-1-117-2015, 2015.
Cerdà, A.: The influence of aspect and vegetation on seasonal changes in
erosion under rainfall simulation on a clay soil in Spain, Can. J. Soil
Sci., 78, 321–330, 1998.
Chakraborty, D., Garg, R. N., Tomar, R. K., Singh, R., Sharma, S. K., Singh,
R. K., Trivedi, S. M., Mittal, R. B., Sharma, P. K., and Kamble, K. H.:
Synthetic and organic mulching and nitrogen effect on winter wheat (Triticum
aestivum L.) in a semi-arid environment, Agr. Water Manage., 97, 738–748, 2010.
Fan, J., Gao, Y., Wang, Q. J., Malhi, S. S., and Li, Y. Y.: Mulching effects
on water storage in soil and its depletion by alfalfa in the Loess Plateau
of northwestern China, Agr. Water Manage., 138, 10–16, 2014.
Fu, S., Liu, B., Zhang, G., Lu, B., and Ye, Z.: Fish-scale pits reduce
runoff and sediment, T. ASABE, 53, 157–162, 2010.
Gao, M. S., Liao, Y. C., Li, X., and Huang, J. H.: Effects of different
mulching patterns on soil water-holding capacity of non-irrigated apple
orchard in the weibei plateau, Scient. Agricult. Sin., 43, 2080–2087, 2010.
Gao, X. D., Wu, P. T., Zhao, X. N., Shi, Y. G., and Wang, J. W.: Estimating
spatial mean soil water contents of sloping jujube orchards using temporal
stability, Agr. Water Manage., 102, 66–73, 2011.
Gao, X. D., Wu, P. T., Zhao, X. N., Wang, J. W., and Shi, Y. G.: Effects of
land use on soil moisture variations in a semi-arid catchment: implications
for land and agricultural water management, Land Degrad. Dev., 25, 163–172, 2014.
Keesstra, S. D., Bruijnzeel, L. A., and van Huissteden, J.: Meso-scale
catchment sediment budgets: combining field surveys and modeling in the
Dragonja catchment, southwest Slovenia, Earth Surf. Proc. Land., 34, 1547–1561, 2009.
Keesstra, S. D., Geissen, V., van Schaik, L., Mosse, K., and Piiranen, S.:
Soil as a filter for groundwater quality, Curr. Opin. Env. Sust., 4, 507–516, 2012.
Li, P., Zhu, Q. K., Zhao, L. L., Chang, C., and Zhou, Y.: Soil moisture of
fish-scale pit during rainy season in Loess hilly and gully region,
T. Chinese Soc. Agr. Eng., 27, 76-81, 2011.
Li, R., Hou, X. Q., Jia, Z. K., Han, Q. F., Ren, X. L., and Yang, B. P.:
Effects on soil temperature, moisture, and maize yield of cultivation with
ridge and furrow mulching in the rainfed area of the Loess Plateau, China,
Agr. Water Manage., 116, 101–109, 2013.
Li, Q. Y., Fang, H. Y., Sun, L. Y., and Cai, Q. G.: Using the 137Cs
technique to study the effect of soil redistribution on soil organic carbon
and total nitrogen stocks in an agricultural catchment of Northeast China,
Land Degrad. Dev., 25, 350–359, 2014.
Li, X. H., Yang, J., Zhao, C. Y., and Wang, B.: Runoff and sediment from
orchard terraces in southeastern China, Land Degrad. Dev., 25, 184–192, 2014.
Lin, L. R. and Chen, J. Z.: The effect of conservation practices in sloped
croplands on soil hydraulic properties and root-zone moisture dynamics,
Hydrol. Process., 29, 2079–2088, 2015.
Liu, Y., Gao, M. S., Wu, W., Tanveer, S. K., Wen, X. X., and Liao, Y. C.:
The effects of conservation tillage practices on the soil water-holding
capacity of a non-irrigated apple orchard in the Loess Plateau, China, Soil
Till. Res., 130, 7–12, 2013.
Liu, Z., Yao, Z., Huang, H., Wu, S., and Liu, G.: Land use and climate
changes and their impacts on runoff in the Yarlung Zangbo river basin,
China, Land Degrad. Dev., 25, 203–215, 2014.
Ma, L. H., Wu, P. T., and Wang, Y. K.: Spatial distribution of roots in a
dense jujube plantation in the semiarid hilly region of the Chinese Loess
Plateau, Plant Soil, 354, 57–68, 2012.
Ma, L. H., Liu, X. L., Wang, Y. K., and Wu, P. T.: Effects of drip
irrigation on deep root distribution, rooting depth, and soil water profile
of jujube in a semiarid region, Plant Soil, 373, 995–1006, 2013.
McIntyre, B. D., Speijer, P. R., Riha, S. J., and Kizito, F.: Effects of
mulching on biomass, nutrients, and soil water in banana inoculated with
nematodes, Agron. J., 92, 1081–1085, 2000.
Mekonnen, M., Keesstra, S. D., Baartman, J. E., Ritsema, C. J., and Melesse,
A. M.: Evaluating sediment storage dams: Structural off-site sediment
trapping measures in northwest Ethiopia, Cuad. Desarro. Rural, 41, 7–22, 2015a.
Mekonnen, M., Keesstra, S. D., Stroosnijder, L., Baartman, J. E. M., and
Maroulis, J.: Soil conservation through sediment trapping: a review, Land
Degrad. Dev., 26, 544–556, 2015b.
Montenegro, A. A. A., Abrantes, J. R. C. B., De Lima, J. L. M. P., Singh, V.
P., and Santos, T. E. M.: Impact of mulching on soil and water dynamics under
intermittent simulated rainfall, Catena, 109, 139–149, 2013.Moreno-Ramón, H., Quizembe, S. J., and Ibáñez-Asensio, S.: Coffee
husk mulch on soil erosion and runoff: experiences under rainfall simulation
experiment, Solid Earth, 5, 851–862, 10.5194/se-5-851-2014, 2014.Mwango, S. B., Msanya, B. M., Mtakwa, P. W., Kimaro, D. N., Deckers, J., and
Poesen, J.: Effectiveness of mulching under miraba in controlling soil
erosion, fertility restoration and crop yield in the usambara mountains,
tanzania, Land Degrad. Dev., 10.1002/ldr.2332, in press, 2015.Ola, A., Dodd, I. C., and Quinton, J. N.: Can we manipulate root system architecture
to control soil erosion?, SOIL, 1, 603–612, 10.5194/soil-1-603-2015, 2015.
Previati, M., Bevilacqua, I., Canone, D., Ferraris, S., and Haverkamp, R.:
Evaluation of soil water storage efficiency for rainfall harvesting on
hillslope micro-basins built using time domain reflectometry measurements,
Agr. Water Manage., 97, 449–456, 2010.
Ram, H., Dadhwal, V., Vashist, K. K., and Kaur, H.: Grain yield and water
use efficiency of wheat (Triticum aestivum L.) in relation to irrigation
levels and rice straw mulching in North West India, Agr. Water Manage., 128, 92–101, 2013.Sadeghi, S. H. R., Gholami, L., Sharifi, E., Khaledi Darvishan, A., and Homaee, M.:
Scale effect on runoff and soil loss control using rice straw mulch under
laboratory conditions, Solid Earth, 6, 1–8, 10.5194/se-6-1-2015, 2015.
Sas-Paszt, L., Pruski, K., Zurawicz, E., Sumorok, B., Derkowska, E., and
Gluszek, A.: The effect of organic mulches and mycorrhizal substrate on
growth, yield and quality of Gold Milenium apples on M.9 rootstock, Can. J.
Plant Sci., 94, 281–291, 2014.Seutloali, K. E. and Beckedahl, H. R.: Understanding the factors influencing
rill erosion on roadcuts in the south eastern region of South Africa, Solid
Earth, 6, 633–641, 10.5194/se-6-633-2015, 2015.
Siczek, A. and Lipiec, J.: Soybean nodulation and nitrogen fixation in
response to soil compaction and surface straw mulching, Soil Till. Res.,
144, 50–56, 2011.
Suman, S. and Raina, J. N.: Efficient use of water and nutrients through
drip and mulch in apple, J. Plant Nutr., 37, 2036–2049, 2014.
Wang, Q. N., Yi, X. H., Wang, H. S., and Xi, W. M.: Soil moisture regime of
fish-scale pits for land preparation engineering in loess slope
revegetation, Chinese J. Soil Sci., 46, 866–872, 2015.
Yu, B., Stott, P., Di, X. Y., and Yu, H. X.: Assessment of land cover
changes and their effect on soil organic carbon and soil total nitrogen in
daqing prefecture, China, Land Degrad. Dev., 25, 520–531, 2014.Zhang, B. Y., Xu, X. X., and Liu, W. Z.: Soil water condition under
different measures of soil and water conservation in loess hilly and gully
region, T. Chinese Soc. Agr. Eng., 25, 54–58, 2009.
Zhang, P., Wang, Y. K., Zhan, J. W., Wang, X., and Wu, P. T.: Scheduling
irrigation for jujube (Ziziphus jujuba Mill.), Afr. J. Biotechnol., 9, 5694–5703, 2010.
Zhao, G., Mu, X., Wen, Z., Wang, F., and Gao, P.: Soil erosion,
conservation, and Eco-environment changes in the Loess Plateau of China,
Land Degrad. Dev., 24, 499–510, 2013.
Zhao, X. N., Wu, P. T., Gao, X. D., Tian, L., and Li, H. C.: Changes of soil
hydraulic properties under early-stage natural vegetation recovering on the
Loess Plateau of China, Catena, 113, 386–391, 2014.
Zhao, X. N., Wu, P. T., Gao, X. D., and Persaud, N.: Soil quality indicators
in relation to land use and topography in a small catchment on the Loess
Plateau of China, Land Degrad. Dev., 26, 54–61, 2015.