Growth of stand average DBH is discussed bassed on relationship between standgrowth and stand density.Growth equation of stand average DBH is fitted with data of 65 plotsand 130 stem analyses of site index 18 meter of...Growth of stand average DBH is discussed bassed on relationship between standgrowth and stand density.Growth equation of stand average DBH is fitted with data of 65 plotsand 130 stem analyses of site index 18 meter of old-growth Larch(Larix gmeliniiRupr.)collectedin Great Xing’an Mountain m Inner Monglia.Variable-density yield tables of old—growth Larchare constructed based on growth equation of stand average DBH and relationship between standaverage DBH and the other stand attributes.展开更多
The development and rc research condition about yield table in China were in-troduced in this paper.Several methods of constructing yield table were also described and studied in brief.
This study aims to characterize water table fluctuations and estimate groundwater recharge in the Tougou catchment located in the Sahel zone of Burkina Faso.Water table fluctuation and groundwater budget approaches ar...This study aims to characterize water table fluctuations and estimate groundwater recharge in the Tougou catchment located in the Sahel zone of Burkina Faso.Water table fluctuation and groundwater budget approaches are developed on an experimental site equipped with observation wells.The trends of water fluctuations in the different layers of the weathering profile are similar.There is a time-lag response of groundwater recharge to the daily precipitation occurrences.The interaction between the upper(clayey alteration)and lower(transition zone-fractured schist complex)parts of the weathering profile shows that generally the hydraulic head in the upper part is higher than that of the lower part due to difference in drainage porosity.The latter varies at the catchment scale between 0.006 and 0.009 and is inversely proportional to the saturated thickness of the clayey alteration layer.The groundwater recharge is annually estimated between 36 and 49 mm,which correspond to 6%and 9%of mean annual rainfall in the catchment.Annual evapotranspiration was estimated to be about 223 to 443 mm.展开更多
Differences in transpiration and leaf water potential （LWP） in relation to cassava yield were investigated along inland valley toposequence in a 4×4 Latin square design. The landrace with the highest transpirat...Differences in transpiration and leaf water potential （LWP） in relation to cassava yield were investigated along inland valley toposequence in a 4×4 Latin square design. The landrace with the highest transpiration rate and lowest LWP yielded the lowest, while TMS 91/02324 and TMS 91/02327 with intermediate rate and highest LWP yielded the highest, indicating that high transpiration rate associated with low LWP reduced yield. Transpiration was lower in the fringe with deeper water table than valley bottom at deep water table site, while at shallow water table, it was higher in the fringe than valley bottom, suggesting that drought and excess moisture reduced transpiration. LWP and water table depth correlated negatively indicating that shallow water table reduced transpiration by reducing LWP. Transpiration increased and LWP decreased as radiation, leaf temperature and vapour pressure deficit increased and differences in these microclimatic conditions caused differences in the two processes between sites, years and time of day. Under mild water stress, transpiration and LWP were higher in the afternoon than the morning, but the reverse occurred under severe stress. TMS 91/02324 and TMS 91/02327 had the highest LWP under severe stress, indicating their higher drought tolerance than the other cultivars.展开更多
文摘Growth of stand average DBH is discussed bassed on relationship between standgrowth and stand density.Growth equation of stand average DBH is fitted with data of 65 plotsand 130 stem analyses of site index 18 meter of old-growth Larch(Larix gmeliniiRupr.)collectedin Great Xing’an Mountain m Inner Monglia.Variable-density yield tables of old—growth Larchare constructed based on growth equation of stand average DBH and relationship between standaverage DBH and the other stand attributes.
文摘The development and rc research condition about yield table in China were in-troduced in this paper.Several methods of constructing yield table were also described and studied in brief.
文摘This study aims to characterize water table fluctuations and estimate groundwater recharge in the Tougou catchment located in the Sahel zone of Burkina Faso.Water table fluctuation and groundwater budget approaches are developed on an experimental site equipped with observation wells.The trends of water fluctuations in the different layers of the weathering profile are similar.There is a time-lag response of groundwater recharge to the daily precipitation occurrences.The interaction between the upper(clayey alteration)and lower(transition zone-fractured schist complex)parts of the weathering profile shows that generally the hydraulic head in the upper part is higher than that of the lower part due to difference in drainage porosity.The latter varies at the catchment scale between 0.006 and 0.009 and is inversely proportional to the saturated thickness of the clayey alteration layer.The groundwater recharge is annually estimated between 36 and 49 mm,which correspond to 6%and 9%of mean annual rainfall in the catchment.Annual evapotranspiration was estimated to be about 223 to 443 mm.
文摘Differences in transpiration and leaf water potential （LWP） in relation to cassava yield were investigated along inland valley toposequence in a 4×4 Latin square design. The landrace with the highest transpiration rate and lowest LWP yielded the lowest, while TMS 91/02324 and TMS 91/02327 with intermediate rate and highest LWP yielded the highest, indicating that high transpiration rate associated with low LWP reduced yield. Transpiration was lower in the fringe with deeper water table than valley bottom at deep water table site, while at shallow water table, it was higher in the fringe than valley bottom, suggesting that drought and excess moisture reduced transpiration. LWP and water table depth correlated negatively indicating that shallow water table reduced transpiration by reducing LWP. Transpiration increased and LWP decreased as radiation, leaf temperature and vapour pressure deficit increased and differences in these microclimatic conditions caused differences in the two processes between sites, years and time of day. Under mild water stress, transpiration and LWP were higher in the afternoon than the morning, but the reverse occurred under severe stress. TMS 91/02324 and TMS 91/02327 had the highest LWP under severe stress, indicating their higher drought tolerance than the other cultivars.
