| 1 | Effects of cellulase and xylanase enzymes mixed with increasing doses of Salix babylonica extract on in vitro rumen gas production kinetics of a mixture of corn silage with concentrate显示文摘An in vitro gas production(GP) technique was used to investigate the effects of combining different doses of Salix babylonica extract(SB) with exogenous fibrolytic enzymes(EZ) based on xylanase(X) and cellulase(C), or their mixture(XC; 1:1 v/v) on in vitro fermentation characteristics of a total mixed ration of corn silage and concentrate mixture(50:50, w/w) as substrate. Four levels of SB(0, 0.6, 1.2 and 1.8 m L g–1 dry matter(DM)) and four supplemental styles of EZ(1 μL g–1 DM; control(no enzymes), X, C and XC(1:1, v/v) were used in a 4×4 factorial arrangement. In vitro GP(m L g–1 DM) were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant p H was determined, and then filtered to determine dry matter degradability(DMD). Fermentation parameters, such as the 24 h gas yield(GY24), in vitro organic matter digestibility(OMD), metabolizable energy(ME), short chain fatty acid concentrations(SCFA), and microbial crude protein production(MCP) were also estimated. Results indicated that there was a SB?EZ interaction(P<0.0001) for the asymptotic gas production(b), the rate of gas production(c), GP from 6 to 72 h, GP2(P=0.0095), and GP4(P=0.02). The SB and different combination of enzymes supplementation influenced(P<0.001) in vitro GP parameters after 12 h of incubation; the highest doses of SB(i.e., 1.8 m L g–1 DM), in the absence of any EZ, quadratically increased(P<0.05) the initial delay before GP begins(L) and GP at different incubation times, with lowering b(quadratic effect, P<0.0001) and c(quadratic effect, P<0.0001; linear effect, P=0.0018). The GP was the lowest(P<0.05) when the highest SB level was combined with cellulose. There were SB?EZ interactions(P<0.001) for OMD, ME, the partitioning factor at 72 h of incubation(PF72), GY24, SCFA, MCP(P=0.0143), and p H(P=0.0008). The OMD, ME, GY24 and SCFA with supp lementation of SB extract at 1.8 m L g–1 DM were higher(P<0.001) than the other treatments, however,PF72 was lower(quadratic effect, P=0.0194) than the other levels. Both C and X had no effect(P>0.05) on OMD, p H, ME, GY24, SCFA and MP. The combination of SB with EZ increased(P<0.001) OMD, ME, SCFA, PF72 and GP24, whereas there was no impact on p H. It could be concluded that addition of SB extract, C, and X effectively improved the in vitro rumen fermentation, and the combination of enzyme with SB extract at the level of 1.2 m L g–1 was more effective than the other treatments. | Abdelfattah Z M Salem German Buendía-Rodríguez Mona M M Elghandour María A Mariezcurrena Berasain Francisco J Pea Jiménez Alberto B Pliego Juan C V Chagoyán María A Cerrillo Miguel A Rodríguez | 2015 | Journal of Integrative Agriculture2015，14，1： | 4 |
| 2 | Land cover changes and fragmentation in mountain neotropical ecosystems of Oaxaca, Mexico under community forest management显示文摘Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control. | Rafael M~a Navarro Cerrillo Dennis J.Esteves Vieira Susana Ochoa-Gaona Bernardus H.J.de Jong M~a del Mar Delgado Serrano | 2019 | Journal of Forestry Research2019，30，1： | 4 |
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