scholarly journals Influence of Land Use Patterns on Evapotranspiration and Its Components in a Temperate Grassland Ecosystem

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Yuzhe Li ◽  
Jiangwen Fan ◽  
Zhongmin Hu ◽  
Quanqin Shao ◽  
Liangxia Zhang ◽  
...  

To better understand variation in response of components of ecosystem evapotranspiration (ET) to grassland use differences, we selected three typical land use patterns in a temperate steppe area: grazed steppe (G), steppe with grazers excluded (GE), and steppe cultivated to cropland (C). ET was divided into its components evaporation (E) and canopy transpiration (T) using herbicide and a chamber attached to a portable infrared gas analyzer (Li-6400). The results indicated that daily water consumption by ET in G was 3.30 kg m−2d−1; compared with G, ET increased significantly in GE at 13.4% and showed a trend of 6.73% increase in C. Daily water consumption by E increased 24.3% in GE relative to G, and C showed 20.2% more than GE. At 0.46, E/ET in C was significantly higher than G at 0.35. Air temperature and the vapor pressure deficit were closely correlated with variation in diurnal ET, E, and T. The leaf area index (LAI) was also positively correlated with daily ET and E varied among grassland use patterns and explained variation in E/ET (81%). Thus, variation in LAI strongly influences the overall magnitude of ecosystem ET and the composition of its components under different grassland use patterns.

2020 ◽  
Vol 111 (1) ◽  
pp. 68-86
Author(s):  
Qingfeng Guan ◽  
Sijing Cheng ◽  
Yongting Pan ◽  
Yao Yao ◽  
Wen Zeng

ZOOTEC ◽  
2015 ◽  
Vol 35 (2) ◽  
pp. 86
Author(s):  
Alfred Tamawiwy ◽  
M. Najoan ◽  
J S Mandey ◽  
F. N Sompie

ABSTRACT   EFFECT OF UTILIZATION OF VIRGIN COCONUT OIL (VCO) IN THE DIET ON PIG PERFORMANCE. Utilization of fats and oils in pig diets is of great importance due to their high energy value. VCO is obtained by cold press processing of the kernel from the coconut fruit. Utilization of virgin coconut oil (VCO) in the diets on pig performance.  The present study was designed to elaborate the effect of utilization of VCO in the diets on energy and protein digestibility of growing pigs. The experiment was conducted using 20 castrated male pigs aged 1.5 - 2.0 months weighing 12,0±2,0 kg. The data were analyzed according to the linear model procedure for ANOVA appropriate for Randomized Block Design with 5 treatments and 4 replications. Treatments were formulated as follow: R0 = 100% control diet + 0% VCO; R1 = 99.5% control diet + 1.0% VCO; R2 = 98.0% control diet + 2.0% VCO; R3 = 97.0% control diet + 3.0% VCO; and R4 = 96.0% control diet + 4.0% VCO. Parameters measured were: daily feed intake, daily gain, daily water consumption. The results showed that the utilization of VCO up to 4% in the diets had no significant effect (P > 0.05) on daily feed intake, daily gain, daily water consumption of pigs. It can be concluded that the addition of VCO up to 4.0% in the diets has no significant meaning on pig performance.   Key words: Virgin coconut oil (VCO), Performance, Growing pigs  


1993 ◽  
Vol 14 (1) ◽  
pp. 25-42 ◽  
Author(s):  
Jordan E. Kerber

Selecting an effective archaeological survey takes careful consideration given the interaction of several variables, such as the survey's goals, nature of the data base, and budget constraints. This article provides justification for a “siteless survey” using evidence from a project on Potowomut Neck in Rhode Island whose objective was not to locate sites but to examine the distribution and density of prehistoric remains to test an hypothesis related to land use patterns. The survey strategy, random walk, was chosen because it possessed the advantages of probabilistic testing, as well as the ease of locating sample units. The results were within the limits of statistical validity and were found unable to reject the hypothesis. “Siteless survey” may be successfully applied in similar contexts where the distribution and density of materials, as opposed to ambiguously defined sites, are sought as evidence of land use patterns, in particular, and human adaptation, in general.


2021 ◽  
Vol 13 (4) ◽  
pp. 631
Author(s):  
Kyle D. Woodward ◽  
Narcisa G. Pricope ◽  
Forrest R. Stevens ◽  
Andrea E. Gaughan ◽  
Nicholas E. Kolarik ◽  
...  

Remote sensing analyses focused on non-timber forest product (NTFP) collection and grazing are current research priorities of land systems science. However, mapping these particular land use patterns in rural heterogeneous landscapes is challenging because their potential signatures on the landscape cannot be positively identified without fine-scale land use data for validation. Using field-mapped resource areas and household survey data from participatory mapping research, we combined various Landsat-derived indices with ancillary data associated with human habitation to model the intensity of grazing and NTFP collection activities at 100-m spatial resolution. The study area is situated centrally within a transboundary southern African landscape that encompasses community-based organization (CBO) areas across three countries. We conducted four iterations of pixel-based random forest models, modifying the variable set to determine which of the covariates are most informative, using the best fit predictions to summarize and compare resource use intensity by resource type and across communities. Pixels within georeferenced, field-mapped resource areas were used as training data. All models had overall accuracies above 60% but those using proxies for human habitation were more robust, with overall accuracies above 90%. The contribution of Landsat data as utilized in our modeling framework was negligible, and further research must be conducted to extract greater value from Landsat or other optical remote sensing platforms to map these land use patterns at moderate resolution. We conclude that similar population proxy covariates should be included in future studies attempting to characterize communal resource use when traditional spectral signatures do not adequately capture resource use intensity alone. This study provides insights into modeling resource use activity when leveraging both remotely sensed data and proxies for human habitation in heterogeneous, spectrally mixed rural land areas.


2019 ◽  
Vol 24 (1) ◽  
pp. 18 ◽  
Author(s):  
Eun-Sun Park ◽  
Yeon-Kyung Lee ◽  
Mi-Hyun Kim ◽  
Mi-Kyeong Choi

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