Papers by Keyword: Soil Moisture

Abstract: Water is the main requirement for the agricultural crops. However, improper amount of water can disturb the plant growth. In modern agriculture, this issue can be tackled by providing the appropriate amount of water for the plant. One of the methods is automatic control system based on the type of physical variables, which indicates water needs for plants [1]. Physical variables that are frequently used as an indicator are temperature and soil moisture [2].The automatic control system can also be applied in agricultural areas that have less water availability. This is due to the automatic control system can help saving water and operating costs [3]. Efforts in building optimal and efficient automated control system can be easily done with complete access to information. One way to access the information control system is via wireless communications [3,4]. From some of these challenges an automatic control system will be built on the research for controlling irrigation in telemetry based on temperature and soil moisture.

Abstract: Effect of different amount sandy soil amendment on soil moisture and millet growth was studied in a rainfed field experiment in a semi-arid region in northern China in 2011-2013. Three-year results show: sandy soil amendment treatments all increased soil moisture, they are T3>T4>T5>T2>T1>CK, and with depth of soil layer increasing, differences of among treatments reduced; it can significantly (P<0.05) increased plant height of millet and dry matter accumulation above-ground by 1.77%-25.67% and 3.21%-104.79% respectively compared with CK; grain yield under sandy soil amendment is significantly (P<0.05) higher than CK, yield of 18000 kg·hm^-2 and 24000 kg·hm^-2 treatments is higher than others,being 5102.55 kg·hm^-2 and 5035.85 kg·hm^-2, biological yield, water and fertilizer use efficiency have the same effect as grain yield. Above all, using sandy soil amendment can improve the condition of soil moisture and fertilizer, sufficiently use limited rainfall, increase crop yield, increases water and fertilizer use efficiency, treatments with 18000 kg·hm^-2,24000 kg·hm^-2 sandy soil amendment show a better effect on resisting drought, retaining fertilizer and increasing yield under millet production in all the treatments.

Abstract: In this paper, the correlation between fused data and original data, the measured soil and the precipitation data over Huaihe river basin by exploring the inversion of soil moisture from the time and space based on the method of multi-source remote sensing data fusion has been studied. In order to fuse the AMSR-E data which is all-day and all-weather and can penetrate the earth surface to some extent, with the MODIS data that can reflect the surface condition and temperature characteristics, the method of wavelet fusion was carried out in MATLAB. The conclusions of this study are listed as follows: (1) the inversion result of the fused data based on AMSE-E and MODIS is much better than a single remote sensing data inversion; (2) the fused data based on AMSE-E and MODIS is sensitive to soil moisture change trend when the seasons alternated every year, especially in the spring, summer and autumn.

Abstract: This paper explores the incidence of hardpans in a field of 14.27 ha. Emphasis is placed on winter wheat yield and its comparison with hardpan location. The objective of this study was to determine prescriptions of different tillage depths for a precision tillage map. In order to meet the above objectives, laboratory and field experiments were conducted based on the experiment design with 60 monitoring points. The results of experiments confirmed the within-field spatial variability of hardpans and crop yield and revealed areas where yield is influenced by detrimental compaction.

Abstract: The soil moisture of three typical P. edulis forests (P. edulis and Cunninghamia lanceolata mixed forest, P. edulis pure forest , P. edulis and broad-leaved tree mixed forest ) in the North of Fujian province were studied in comparison with C. lanceolata pure forest and evergreen broad-leaved forest. Based on the routine observation, characteristics of spatial and temporal change of soil water content were studied. According to the roots distribution which were analyzed on different forest stand, the Linear and relationship model were established about the soil water and roots distribution. Results showed that the forest stand roots density decreasing with increasing soil depth, roots density and spatial distribution of soil moisture are related closely.

Abstract: [Objective] Soil moisture is the key factor of highway greening. To maintain the steady and sustainable development of highway greening, the problem of soil moisture should be primarily solved. [Method] In this paper, the dynamic variation law of highway slope’s soil moisture was studied by the continuous observation of the soil moisture (0~40cm) and rainfall in all points (sunny slope, shade slope, ground, and the central partition belt) of China’s Langfang—Zhuozhou Highway from April to November 2009. [Result] From April to May, the soil moisture content declined continuously. From May to August, the soil moisture content increased rapidly and also was kept at a higher level. From August to October, the soil moisture content declined gradually. From October to November, the soil moisture content increased steadily. The soil moisture in the surface (0~10cm) and the lower layer (10cm~20cm) fluctuated greatly, and the variation coefficient was 28.39% and 24.85% respectively; the change of the soil moisture content in the deep layer (20cm~40 cm) decreased significantly, and the variation coefficient was 19.41%. [Conclusion] The seasonal dynamic variation law of highway slope’s soil moisture is significant, and also keeps consistent with the dynamic rainfall, plant transpiration, and soil evaporation laws. The soil moisture conditions from May to August are the best. The spatial variation of the soil moisture can be divided into two layers: the rapid-variation layer (0~20 cm) and the active layer (20cm~40 cm). In each observation point, the soil moisture conditions are the best in the central partition belt, secondary in the sunny and shade slopes, and the worst in ground.

Abstract: Matrix suction is very important in researching the properties of unsaturated soil. At present, there have been a lot of measurements of matrix suction. Basing on the physical principles of each kind of measurements, this paper divides them into indoor test method and field test method and evaluates them by equipment needed, operation steps, measurement range and matters needing attention.

Abstract: This study was carried on about soil moisture and nutrients of meadow steppe, typical steppe and desert steppe ecosystems. The results showed that meadow steppes had the maximum soil moisture content, while the desert steppes had the minimum. This was because the three types of steppes had different soil types and physical characteristics, and these physical characteristics influenced soil moisture content to some extent. Compared with that in the meadow steppes and desert steppes, carbon and nitrogen content of soil of the typical steppes were the highest, and the differences in soil carbon and nitrogen among the three types of steppes were significant or obviously significant. They were due to the geographical environments, temperature and precipitation caused by a combination of factors.

Abstract: Soil moisture content and soil porosity were measured in banana plantation under three tillage practices, including deep-tillage (DT), no-tillage (NT), and no-tillage plus straw cover (NTSC). In the experiments, the top layer soil was separated into three depth including 0~15 cm, 15~30 cm and 30 ~ 45 cm. The soil sampling were performed at four plant growth periods, including the stage of banana seedling (SBS), metaphase of banana (MB), the stage of pregnancy (SP) and pumping stage (PS). The results showed that: Among three depth of top layers, soil moisture content in 0~15 cm at four plant growth periods was lower than that in other two depth by three tillage practices. In 0~15 cm top layer soil, all the soil moisture at four plant periods by NTSC practice were highest. And all the soil moisture in soil treated by three tillage practices were increased with the plant growth. The soil porosity in this layer at SBS and MB stages by DT practice was significantly higher than that by NT and NTSC practices. In 15~30 cm layer soil, the soil moisture content and soil porosity at SBS stage was highest in the soil treated by DT practice compared to the that in soil treated by other two tillage practices. In 30~45 cm layer, the soil porosity at SBS stage by DT and NTSC practices were significantly lower than that by NT practice. At MB stage by DT practice it was significantly higher than that by other practices.

Abstract: Soil profiles from 0 to 80 cm depth were collected and a 14-day incubation experiment at three soil moisture levels (initial moisture, water holding capacity, and flooding) was carried out at 25°C in the dark to reveal the effects of soil moisture on nitrogen mineralization rates in a 10-yr floodplain wetland. Our results showed that nitrogen mineralization rates decreased with depth along soil profiles and the maximal nitrogen mineralization rates appeared at the 10-20cm soil layer. The nitrogen mineralization rates were higher under flooding treatment compared to another two soil moisture treatments. Nitrogen mineralization rates in the top 20cm soils exhibited an increasing tendency with increasing soil moisture. Additionally, nitrogen mineralization rates were significantly correlated with electrical conductivity, total soluble salt, and salinity under three soil moisture treatments.