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Water ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 3333
Author(s):  
Detlef Deumlich ◽  
Lidia Völker ◽  
Roger Funk ◽  
Tobias Koch

The topography is one of the determining site characteristics, of which the slope inclination is significant for natural science aspects, including the estimation of water erosion risk and as a criterion for agricultural subsidies. The slopes within an area vary greatly and occupy very different proportions of the area. Algorithms that take this heterogeneity into account were developed in the 1970s with the medium-scale agricultural site mapping (MMK). It also contains the slope association types (SAT, in German: “Hangneigungsflächentyp”), which classifies different slopes and summarizes them as one value per reference area. The SAT can be used across various scales and different targets. Applicability is given to soil and water conservation tasks, administrative tasks as field selection or agricultural subsidies, and over a wide range of scales from small catchments areas to whole landscape analyses. Thus, one value on an area basis characterizes an important topographic factor.


2021 ◽  
Vol 66 (3) ◽  
Author(s):  
Regatti Venkat

Rotary weeder cum fertilizer drill accomplishes both the operations of weeding and fertilizer application simultaneously in a single operation. Performance of developed machine was evaluated in castor crop. Cost has been worked out as per the standard procedure and comparison made in terms of labour saving to determine the economic feasibility of the machines. It had been estimated that the break-even point (BEP) calculated on time and area basis for rotary weeder cum fertilizer drill was 273 h and 53.50 ha, respectively. The payback period calculated on time basis for the rotary weeder- cum- fertilizer drill was found to be a little over 3 years. Cost of weeding and fertilizer drilling through rotary weeder- cum- fertilizer drill can save cost up to 34.22 per cent as compared to the combined cost of existing methods of weeding and fertilizer application methods.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. S. Ladaniya ◽  
R. A. Marathe ◽  
A. A. Murkute ◽  
A. D. Huchche ◽  
A. K. Das ◽  
...  

AbstractHigh density planting system i.e. accommodating a higher number of plants than routine in a given area is an innovative agro-technology to increase yield and thereby early net returns. Due to conventional wide spacing plantation in Nagpur mandarin (Citrus reticulata Blanco), the land remains unutilized as the plant canopy gradually increases over the years. In the present study, Nagpur mandarin (Citrus reticulata Blanco) budded on Rangpur lime rootstock was evaluated under six different planting spacings. It was observed that the organic carbon (1.10–1.82%) and major nutrients viz. N (309–430 kg ha−1), P (20–54 kg ha−1) and K (291–810 kg ha−1) increased vis-à-vis plant density and was highest under 2 × 2 m spacing. Plants were tallest at 2 × 2 m spacing with the higher PAR interception (88.2) and the lowest leaf area index (1.09). Fruit yield on area basis, under 2 × 2 m spacing was 26, 7.1, 4.6 times more as compared to conventional plantation during the first, second and third year, respectively. At fifth year of crop harvest, the highest B:C ratio (6.36) was recorded in 6 × 3 m followed by 4 × 2 m and 2 × 2 m.


Author(s):  
Yoshiaki Nomura ◽  
Yoshimasa Ishii ◽  
Yota Chiba ◽  
Shunsuke Suzuki ◽  
Akira Suzuki ◽  
...  

The increasing healthcare cost imposes a large economic burden for the Japanese government. Predicting the healthcare cost may be a useful tool for policy making. A database of the area-basis public health insurance of one city was analyzed to predict the medical healthcare cost by the dental healthcare cost with a machine learning strategy. The 30,340 subjects who had continued registration of the area-basis public health insurance of Ebina city during April 2017 to September 2018 were analyzed. The sum of the healthcare cost was JPY 13,548,831,930. The per capita healthcare cost was JPY 446,567. The proportion of medical healthcare cost, medication cost, and dental healthcare cost was 78%, 15%, and 7%, respectively. By the results of the neural network model, the medical healthcare cost proportionally depended on the medical healthcare cost of the previous year. The dental healthcare cost of the previous year had a reducing effect on the medical healthcare cost. However, the effect was very small. Oral health may be a risk for chronic diseases. However, when evaluated by the healthcare cost, its effect was very small during the observation period.


HortScience ◽  
2020 ◽  
Vol 55 (10) ◽  
pp. 1558-1566
Author(s):  
Tamara Wynne ◽  
Dale Devitt

Irrigation in arid urban landscapes can use significant amounts of water. Water conservation must be based on plant species and the ability to meet plant water requirements while minimizing overirrigation. However, actual evapotranspiration (ET) estimates for landscape trees and turfgrass in arid environments are poorly documented, especially direct comparisons to assess potential trade-offs. We conducted research to quantify ET of 10 common landscape tree species grown in southern Nevada and compared these values with the ET of both a warm season and cool season turfgrass species. The trees were grown in a plot with a high-density planting (256 trees/ha). A complete morphological assessment was made on each tree, and monitoring of plant water status was conducted monthly. ET was quantified with a hydrologic balance approach, irrigating based on the previous week’s ET to eliminate a drainage component. Transpiration was estimated with sap-flow sensors, and evaporation was estimated by difference. Although ET in liters revealed no statistical difference based on species, there were many significant differences in tree morphological parameters (P < 0.05), such as found with basal canopy area. When ET was converted to centimeters based on standardizing the ET on a basal canopy area basis, statistically higher ET values (P < 0.05) were generated for three of the trees (Lagerstroemia indica, Gleditsia tricanthos, and Fraxinus velutina ‘Modesto’). A clear separation of all tree ET values (lower ET) with turfgrass ET occurred (P < 0.001), with the exception of L. indica. Backward regression analysis revealed that all morphological and physiological parameters were eliminated with the exception of percent cover in predicting ET (cm, R2 = 0.88, P < 0.001). In addition, a highly curvilinear relationship existed between decreasing percent tree cover and ET on a basal canopy area basis (R2 = 0.96, P < 0.001), revealing that smaller trees located within the plot had significantly higher ET (centimeters). Tree-to-grass water use ratios demonstrated that all species except L. indica had ratios significantly below 1.0, indicating that on the basis of this study, landscapes dominated by mature trees irrigated at ET would have lower water use rates than similar areas planted to turfgrass, with the exception of the smaller L. indica. The results suggest that the smaller trees within the higher planting density plot were partially released from a negative feedback on transpiration that occurred in the larger trees based on reduced canopy atmospheric coupling.


2020 ◽  
Vol 12 (18) ◽  
pp. 2958
Author(s):  
Gustavo Togeiro de Alckmin ◽  
Arko Lucieer ◽  
Gerbert Roerink ◽  
Richard Rawnsley ◽  
Idse Hoving ◽  
...  

Crude protein estimation is an important parameter for perennial ryegrass (Lolium perenne) management. This study aims to establish an effective and affordable approach for a non-destructive, near-real-time crude protein retrieval based solely on top-of-canopy reflectance. The study contrasts different spectral ranges while selecting a minimal number of bands and analyzing achievable accuracies for crude protein expressed as a dry matter fraction or on a weight-per-area basis. In addition, the model’s prediction performance in known and new locations is compared. This data collection comprised 266 full-range (350–2500 nm) proximal spectral measurements and corresponding ground truth observations in Australia and the Netherlands from May to November 2018. An exhaustive-search (based on a genetic algorithm) successfully selected band subsets within different regions and across the full spectral range, minimizing both the number of bands and an error metric. For field conditions, our results indicate that the best approach for crude protein estimation relies on the use of the visible to near-infrared range (400–1100 nm). Within this range, eleven sparse broad bands (of 10 nm bandwidth) provide performance better than or equivalent to those of previous studies that used a higher number of bands and narrower bandwidths. Additionally, when using top-of-canopy reflectance, our results demonstrate that the highest accuracy is achievable when estimating crude protein on its weight-per-area basis (RMSEP 80 kg.ha−1). These models can be employed in new unseen locations, resulting in a minor decrease in accuracy (RMSEP 85.5 kg.ha−1). Crude protein as a dry matter fraction presents a bottom-line accuracy (RMSEP) ranging from 2.5–3.0 percent dry matter in optimal models (requiring ten bands). However, these models display a low explanatory ability for the observed variability (R2 > 0.5), rendering them only suitable for qualitative grading.


2018 ◽  
Vol 44 (3) ◽  
pp. 469-473
Author(s):  
MMA Mondal ◽  
MA Malek ◽  
AB Puteh

Twelve modern summer mungbean cultivars were evaluated to assess morpho-physiological characters, yield attributes and seed yield. Results revealed that high yielding cultivars, in general, showed superiority in morpho-physiological characters and seed yield/plant than the low yielding cultivars. However, in case of unit area basis, result revealed that seed yield/ha was greater in low yielding cultivars than the high yielding ones, yet they produced lower seed yield/plant compared to high yielding ones due to increase number of plants per unit area and these low yielding cultivars also matured 10 - 15 days earlier than high yielders. Among the cultivars, BINAmung-5 produced the highest seed yield/ha (1711 kg/ha) with lower HI (20.0%) and took longer days to maturity (69 days). On the other hand, BARImung-6 showed second highest seed yield (1697 kg/ha) with highest HI (32.6%) and matured earliest, took 60 days after sowing that might be fit the existing cropping pattern in Bangladesh.


Author(s):  
A. Dou ◽  
L. Ding ◽  
M. Chen ◽  
X. Wang

The remote sensing has played an important role in many earthquake emergencies by rapidly providing the building damage, road damage, landslide and other disaster information. The earthquake in the mountains often caused to the loosening of the mountains and the blowing of the dust in the epicentre area. The dust particles are more serious in the epicentre area than the other disaster area. Basis on the analysis of abnormal spectrum characteristics, the dust detection methods from medium and high resolutions satellite imagery are studied in order to determinate the extreme earthquake disaster area. The results indicate the distribution of extreme disaster can be acquired using the dust detection information from imagery, which can provide great help for disaster intensity assessment.


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3553 ◽  
Author(s):  
Mary-Rus Martinez-Cuenca ◽  
Amparo Primo-Capella ◽  
Ana Quiñones ◽  
Almudena Bermejo ◽  
Maria Angeles Forner-Giner

Background and aimsThis work evaluates the regulation of iron uptake responses in Citrus leaves and their involvement in the Fe paradox effect.MethodsExperiments were performed in field-grown ‘Navelina’ trees grafted onto two Cleopatra mandarin ×Poncirus trifoliata(L.) Raf. hybrids with different Fe-chlorosis symptoms: 030146 (non-chlorotic) and 030122 (chlorotic).ResultsChlorotic leaves were smaller than non-chlorotic ones for both dry weight (DW) and area basis, and exhibited marked photosynthetic state affection, but reduced catalase and peroxidase enzymatic activities. Although both samples had a similar total Fe concentration on DW, it was lower in chlorotic leaves when expressed on an area basis. A similar pattern was observed for the total Fe concentration in the apoplast and cell sap and in active Fe (Fe2+) concentration.FRO2gene expression and ferric chelate reductase (FC-R) activity were also lower in chlorotic samples, whileHA1andIRT1were more induced. Despite similar apoplasmic pH, K+/Ca2+was higher in chlorotic leaves, and both citrate and malate concentrations in total tissue and apoplast fluid were lower.Conclusion(1) The rootstock influences Fe acquisition system in the leaf; (2) the increased sensitivity to Fe-deficiency as revealed by chlorosis and decreased biomass, was correlated with lower FC-R activity and lower organic acid level in leaf cells, which could cause a decreased Fe mobility and trigger other Fe-stress responses in this organ to enhance acidification and Fe uptake inside cells; and (3) the chlorosis paradox phenomenon in citrus likely occurs as a combination of a marked FC-R activity impairment in the leaf and the strong growth inhibition in this organ.


2016 ◽  
Vol 13 (12) ◽  
pp. 3819-3831 ◽  
Author(s):  
Wenjuan Zhu ◽  
Wenhua Xiang ◽  
Qiong Pan ◽  
Yelin Zeng ◽  
Shuai Ouyang ◽  
...  

Abstract. Leaf area index (LAI) is an important parameter related to carbon, water, and energy exchange between canopy and atmosphere and is widely applied in process models that simulate production and hydrological cycles in forest ecosystems. However, fine-scale spatial heterogeneity of LAI and its controlling factors have yet to be fully understood in Chinese subtropical forests. We used hemispherical photography to measure LAI values in three subtropical forests (Pinus massoniana–Lithocarpus glaber coniferous and evergreen broadleaved mixed forests, Choerospondias axillaris deciduous broadleaved forests, and L. glaber–Cyclobalanopsis glauca evergreen broadleaved forests) from April 2014 to January 2015. Spatial heterogeneity of LAI and its controlling factors were analysed using geostatistical methods and the generalised additive models (GAMs) respectively. Our results showed that LAI values differed greatly in the three forests and their seasonal variations were consistent with plant phenology. LAI values exhibited strong spatial autocorrelation for the three forests measured in January and for the L. glaber–C. glauca forest in April, July, and October. Obvious patch distribution pattern of LAI values occurred in three forests during the non-growing period and this pattern gradually dwindled in the growing season. Stem number, crown coverage, proportion of evergreen conifer species on basal area basis, proportion of deciduous species on basal area basis, and forest types affected the spatial variations in LAI values in January, while stem number and proportion of deciduous species on basal area basis affected the spatial variations in LAI values in July. Floristic composition, spatial heterogeneity, and seasonal variations should be considered for sampling strategy in indirect LAI measurement and application of LAI to simulate functional processes in subtropical forests.


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