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81.
We evaluated the accuracy and efficiency of airborne (ALS), terrestrial (TLS) and mobile laser-scanning (MLS) methods that can be utilized in urban tree mapping and monitoring. In the field, 438 urban trees located in park and forested environments were measured and mapped from our study area located in Seurasaari, Helsinki, Finland. A field reference was collected, using a tree map created manually from TLS data. The tree detection rate and location accuracy were evaluated, using automatic or semiautomatic ALS individual tree detection (ALSITDauto or ALSITDvisual) and manual or automatic measurements of TLS and MLS (TLSauto, MLSauto, MLSmanual, MLSsemi). Our results showed that the best methods for tree detection were TLSauto and MLSmanual, which detected 73.29% and 79.22% of the reference trees, respectively. The location accuracies (RMSE) varied between 0.44 m and 1.57 m; the methods listed from the most accurate to most inaccurate were MLSsemi, TLSauto, MLSmanual, MLSauto, ALSITDauto and ALSITDvisual. We conclude that the accuracies of TLS and ALS were applicable for operational urban tree mapping in heterogeneous park forests. MLSmanual shows high potential but manual measurements are not feasible in operational tree mapping. Challenges that should be solved in further studies include ALSITDauto oversegmentation as well as MLSauto processing methodologies and data collection for tree detection.  相似文献   
82.
Arbuscular mycorrhizal (AM) symbioses may alter the competitive abilities of plant species and facilitate positive interactions such as nutrient transfer between plants. They are therefore particularly interesting components in agroforestry systems. We studied spatial variation of AM colonisation on a cut-and-carry fodder production site (agroforestry plot) of the legume tree Gliricidia sepium and the fodder grass Dichanthium aristatum. Roots of the two plant species were sampled under the tree canopies and on the adjacent grass plot at 1 and 3.5 m from the first tree row where G. sepium roots also occur. Roots of D. aristatum were also sampled on a nearby grass monocrop. Colonisation of arbuscules, vesicles and hyphae in root samples was visually determined, and AM fungal species were identified by DNA sequencing. Colonisation and frequency of types of AM formations varied statistically significantly between the species and sampling points. Arbuscular colonisation in G. sepium roots was higher under the tree canopies than on the adjacent grass plot. Soil nutrient content, particularly P and N, and interspecies competition are the most probable explanations for the observed variation in AM colonisation. Both arbuscular colonisation and arbuscule:vesicle ratio in D. aristatum roots was lower on the D. aristatum monocrop than on the agroforestry plot under or near the tree canopies. Intercropping could stimulate AM symbiosis in D. aristatum. Both plant species formed symbiosis with Rhizophagus intraradices, indicating potential for interplant N transfer via common mycelial networks of AM-forming fungi.  相似文献   
83.
Uncertainty factors related to inventory methodologies and forest-planning simulation computings in the estimation of logging outturn assortment volumes and values were examined. The uncertainty factors investigated were (1) forest inventory errors, (2) errors in generated stem distribution, (3) effects of generated stem distribution errors on the simulation of thinnings and (iv) errors related to the prediction of stem form and simulation of bucking. Regarding inventory errors, standwise field inventory (SWFI) was compared with area-based airborne laser scanning (ALS) and aerial photography inventorying. Our research area, Evo, is located in southern Finland. In all, 31 logging sites (12 clear-cutting and 19 thinning sites) measured by logging machine in winter 2008 were used as field reference data. The results showed that the most significant source of error in the prediction of clear-cutting assortment outturns was inventory error. Errors related to stem-form prediction and simulated bucking as well as generation of stem distributions also cause uncertainty. The bias and root-mean-squared error (RMSE) of inventory errors varied between −11.4 and 21.6 m3/ha and 6.8 and 40.5 m3/ha, respectively, depending on the assortment and inventory methodology. The effect of forest inventory errors on the value of logging outturn in clear-cuttings was 29.1% (SWFI) and 24.7% (ALS). The respective RMSE values related to thinnings were 41.1 and 42%. The generation of stem distribution series using mean characteristics led to an RMSE of 1.3 to 2.7 m3/ha and a bias of −1.2 to 0.6 m3/ha in the volume of all assortments. Prediction of stem form and simulation of bucking led to a relative bias of −0.28 to 0.00 m3 in predicted sawtimber volume. Errors related to pulpwood volumes were −0.4 m3 to 0.21 m3.  相似文献   
84.
85.
Effects of lipid removal on the fine milling and air classification processing of oats were studied. Lipid removal by supercritical carbon dioxide (SC-CO2) extraction enabled concentration of the main components of oats - starch, protein, lipids and cell walls - into specific fractions. Using defatted oats as raw material, the highest β-glucan concentration of the cell wall-enriched fraction was 33.9% as compared to 17.1% without lipid removal. This was probably due to more efficient milling yielding smaller particles, and release of starchy material from cellular structures during milling of defatted oats, resulting in better classification. The removal of lipids also enabled separation of an oat protein concentrate with a protein concentration of 73.0% and a mass yield of 5.0%. A trial with 2310 kg of oat groats showed that the process based on defatting and dry fractionation was also industrially applicable.  相似文献   
86.
The goal of this work was to analyze nutritional value of various minimally processed commercial products of plant protein sources such as faba bean (Vicia faba), lupin (Lupinus angustifolius), rapeseed press cake (Brassica rapa/napus subsp. Oleifera), flaxseed (Linum usitatissimum), oil hemp seed (Cannabis sativa), buckwheat (Fagopyrum esculentum), and quinoa (Chenopodium quinoa). Basic composition and various nutritional components like amino acids, sugars, minerals, and dietary fiber were determined. Nearly all the samples studied could be considered as good sources of essential amino acids, minerals and dietary fiber. The highest content of crude protein (over 30 g/100 g DW) was found in faba bean, blue lupin and rapeseed press cake. The total amount of essential amino acids (EAA) ranged from 25.8 g/16 g N in oil hemp hulls to 41.5 g/16 g N in pearled quinoa. All the samples studied have a nutritionally favorable composition with significant health benefit potential. Processing (dehulling or pearling) affected greatly to the contents of analyzed nutrients.  相似文献   
87.
This study was conducted to compare the effects of electron beam (EB) and gamma ray (GR) irradiation treatments at doses of 10, 20 and 30 kGy on chemical composition, protein quality and protein digestibility of cottonseed meal (CSM). GR irradiation in all doses significantly decreased the crude fiber of samples compared to raw CSM. Free and total gossypol content of CSM was decreased significantly by utilizing both types of irradiation in a dose‐dependent manner. Also, EB irradiation caused decrease in free and total gossypol content more than that of GR irradiation. GR irradiation at doses of 20 and 30 kGy, and EB irradiation at doses of 10, 20 and 30 kGy can significantly decrease protein solubility of CSM compared to that of a raw sample. GR irradiation at a dose of 30 kGy significantly increased apparent digestibility of protein compared to raw and EB irradiation of CSM at a dose of 10 kGy in Leghorn cockerels. Maximum increase in protein digestibility of CSM was observed in GR irradiation at a dose of 30 kGy. In conclusion, the present study showed that EB and GR irradiation reduced gossypol and crude fiber and increased protein digestibility of CSM but had no effect on protein quality of CSM.  相似文献   
88.
The chickpea leaf miner, Liriomyza cicerina (Rondani) (Diptera: Agromyzidae), is an important pest of cultivated chickpea (Cicer arietinum L.). A 2-year field study was carried out to screen a total of 126 Cicer germplasm for resistance to the leaf miner during the 2012 and 2013 growing seasons. Resistance was evaluated using a visual scale of 1–9, where 1?=?highly resistant and 9?=?very highly susceptible under natural infestation conditions. The results showed that two C. arietinum accessions, ILC 3397 and Sierra, had a score of 9 on the scale, being very highly susceptible. Three germplasm, one mutant (3304) and two breeding lines (LMR 140 and LMR 160) of C. arietinum, were found to be highly resistant with the scores ranging from 1.5 to 2 for resistance to the leaf miner. The mutant, 3304, was detected for the first time in this study as a highly leaf miner-resistant mutant of the cultivated chickpeas while the other two breeding lines had been previously reported as highly resistant against the leaf miner. In addition, two mutants and 14 breeding lines of C. arietinum and two mutants and one germplasm of C. reticulatum were identified as resistant having the scores from 2.1 to 3 on the 1–9 scale. The results suggest that these resistant germplasm may add a new dimension to chickpea breeding programs because they possess valuable traits for resistance against the pest. The resistant chickpeas that can be grown without using pesticides are important as environmental protection and reliable food source for human health.  相似文献   
89.
The potential of grafted watermelon for resistance toFusarium oxysporum f.sp.niveum on some Curcurbitaceae,Lagenaria, Luffa, Benincasa and commercial rootstocks was evaluated. Effects of grafting on yield and quality of diseased plants were evaluated. All grafted plants and rootstocks were resistant to the three known races (0, 1, and 2) ofF. oxysporum f.sp.niveum except watermelon cv. ‘Crimson Tide’, which was susceptible to race 2. Fruit yield was positively (21–112%) affected byLagenaria rootstocks but negatively affected (200–267%) byCucurbita rootstocks when compared with the control. While only minor differences in fruit quality were determined in control and grafted plants onLagenaria rootstocks, the quality parameters for watermelon grafted ontoCucurbita rootstocks were lower than in the control. The reasons for low yield and quality might be due to an incompatibility betweenCucurbita rootstocks and watermelon. These results showed that rootstock influence on disease resistance as well as yield and quality of scion fruit is important in determining the potential use of grafting applications in watermelon. http://www.phytoparasitica.org posting Feb. 2, 2003.  相似文献   
90.
Application of organic waste on agricultural land as a soil conditioner and fertilizing material has lately gained much attention. This study was conducted to determine the effects of vermicompost applications (0·5%, 1%, 2% and 4% w/w) on physical characteristics of soils with different textures (sandy loam, loam and clay), under laboratory conditions. The results indicated that in the higher soil aggregate fraction (>12·7 mm) aggregate fraction was limited at the three soils. Vermicompost applications in all three soils significantly increased organic matter content. When compared with control, the increasing rates in organic matter content were 14·0%, 23·8%, 42·0% and 90·2% for 0·5%, 1%, 2% and 4% vermicompost application doses, respectively. Vermicompost applications increased the wet aggregate stability and decreased the dispersion ratio of all the experimental soils in all aggregate size fractions. Overall, wet aggregate stability increased from 26·9% to 52·2% with the application rate of 4%. Correlation coefficient between organic matter content and wet aggregate stability was found as 0·918**. The lowest mean bulk density and the highest mean total porosity occurred when the most vermicompost was added. In all the soils studied, the highest permeability coefficients were gained with the application dose of 2%. As a result of increase in wet aggregate stability and decrease in bulk density, air permeability increased, and penetration resistance decreased significantly. The results obtained in this study have clearly indicated that the vermicompost application is an effective way to improve soil physical characteristics. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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