The nutritive value of rangelands in Southern Darfur, Sudan could be improved by introduction and multiplication of nutritious forbs with the objective of increasing livestock production in the area. The present study...The nutritive value of rangelands in Southern Darfur, Sudan could be improved by introduction and multiplication of nutritious forbs with the objective of increasing livestock production in the area. The present study was conducted to evaluate the nutritive value and palatability of eleven range forbs collected at flowering stage from Gahzal Gawazat, Southern Darfur, Sudan using chemical analysis. The crude protein (CP) ranged from 6.8% in Oxygonum atriplicifolium with lowest digestible crude protein (DCP) 2.8% to 16.4% in Zornia diphylla with highest DCP 11.73%. The highest and the lowest crude fiber (CF) values were obtained in Commelina spp (56.4%) and Sesamum alatum (25.9%), respectively. NDF and DMI values were maximum and minimum for Zornia diphylla (44.9 and 2.67%) and Alysicarpus glumaceus (35.3 and 3.4%), respectively. The total digestible nutrients (TDN) ranged from 57.1% in Blepharis linariifolia to 69.3% in Tribulus terrestris with highest digestible energy (DE) in later while the lowest DE was obtained in Commelina spp (2.4%). The calculated in vitro organic matter digestibility (IVOMD) was highest for the Canavalia ensiformis (50.27%) and lowest value (43.17%) for Commelina spp. Zornia diphylla, Tribulus terrestris and Sesamum alatum showed highest nutritive value, while Alysicarpus glumaceus, Oldenlandia senegalensis and Chrozophora brocchiana showed highest palatability. It is concluded that these rangeland forbs are palatable and their CP and energy contents are sufficient to support different classes of livestock in South Darfur, Sudan.展开更多
Annual growth rings of roots in perennial forbs have been used in studies of climate change and the ecology of grasslands. However, little has been done in this aspect of research in China. In this study, we report th...Annual growth rings of roots in perennial forbs have been used in studies of climate change and the ecology of grasslands. However, little has been done in this aspect of research in China. In this study, we report the characteristics of growth rings in the main roots of 13 herb species sampled in Duolun of the Inner Mongolia grassland in northern China. The results show that around two thirds of the species possess clearly demarcated annual rings in the root xylem. Some species of the same genera show different patterns in anatomical structure of the root xylem. Standardized annual ring widths of three species, Potentilla anserine L., Cymbaria dahurica L. and Lespedeza daurica (Laxm.) Schindh, show a common linear trend, indicating a continued favorable growth condition in the sampling sites. Our results provide evidence that growth rings in roots of some perennial forbs in the Inner Mongolia grassland can serve as a new and useful indicator of past changes in the grassland environment.展开更多
Fire is a natural disturbance occurring every few years in many grasslands ecosystems. However, since European colonization, fire has been highly reduced or even suppressed in Argentinean grasslands, fostering ignitab...Fire is a natural disturbance occurring every few years in many grasslands ecosystems. However, since European colonization, fire has been highly reduced or even suppressed in Argentinean grasslands, fostering ignitable material accumulation. This has led to occasional catastrophic controldemanding fire events, extended for larger areas. The aims of this work are to study vegetation recovery and change after a non-natural fire event in mountain grasslands. The study area is located in the Ventania mountain system, mid-eastern Argentina. We studied vegetation recovery after fire(January 2014) in two different communities: grass-steppes(grasslands) and shrub-steppes(open low shrublands). We measured vegetation cover, species richness and bare ground percentage in burned and unburned areas 1, 4, 8, 11 and 23 months after fire. Vegetation surveys were also performed at the end of the growing season(December) 11 and 23 months after fire. Data were analyzed using regression analysis, ANOVA and multivariate analysis(NMS, PERMANOVA). Both communities increased their vegetation cover at the same rate, without differences between burned and unburned areas after two years. Species richness was higher in shrublands and their recovery was alsofaster than in grasslands. Considering functional composition, besides transient changes during the first year after fire, there were no differences in abundance of different functional vegetation groups two years after fire. At the same time, shrublands showed no differences in species composition, while grasslands had a different species composition in burned and unburned plots. Also, burned grassland showed a higher species richness than unburned grassland. Data shown mountain vegetation in Pampas grassland is adapted to fire, recovering cover and richness rapidly after fire and thus reducing soil erosion risks. Vegetation in mountain Pampas seems to be well adapted to fire, but in grasslands species composition has changed due to fire. Nonetheless, these changes seem to be not permanent since prefire species are still present in the area.展开更多
福布斯最新发布的"亚洲地区30位30岁以下领袖榜"(Forbes 30 Under 30 Asia)中,来自上海热巢网络科技有限公司(下称"热巢")的两位创始人——穆青与他的德国小伙伴Fabian von Heimburg当选广告与传媒领域青年领袖。对穆青来说,这...福布斯最新发布的"亚洲地区30位30岁以下领袖榜"(Forbes 30 Under 30 Asia)中,来自上海热巢网络科技有限公司(下称"热巢")的两位创始人——穆青与他的德国小伙伴Fabian von Heimburg当选广告与传媒领域青年领袖。对穆青来说,这份荣誉来得并不突然。早在2016年10月,德国总理默克尔访华期间与李克强总理共同讨论德国工业4.0和中国制造2025时,热巢作为唯一中德创新创业企业被邀请参加。这让穆青引以为豪。展开更多
在《福布斯》杂志(Forbes)公布的2011年美国大学排行榜中,有三所美国军事院校名列前二十,其中名列第三的是西点军校(United States Military Academy,即美国军校),排名比哈佛大学还要高(名列第六);紧随在名列第九的麻省理工学院之后的...在《福布斯》杂志(Forbes)公布的2011年美国大学排行榜中,有三所美国军事院校名列前二十,其中名列第三的是西点军校(United States Military Academy,即美国军校),排名比哈佛大学还要高(名列第六);紧随在名列第九的麻省理工学院之后的是排名第十的美国空军军校(United States Air Force Academy);展开更多
文摘The nutritive value of rangelands in Southern Darfur, Sudan could be improved by introduction and multiplication of nutritious forbs with the objective of increasing livestock production in the area. The present study was conducted to evaluate the nutritive value and palatability of eleven range forbs collected at flowering stage from Gahzal Gawazat, Southern Darfur, Sudan using chemical analysis. The crude protein (CP) ranged from 6.8% in Oxygonum atriplicifolium with lowest digestible crude protein (DCP) 2.8% to 16.4% in Zornia diphylla with highest DCP 11.73%. The highest and the lowest crude fiber (CF) values were obtained in Commelina spp (56.4%) and Sesamum alatum (25.9%), respectively. NDF and DMI values were maximum and minimum for Zornia diphylla (44.9 and 2.67%) and Alysicarpus glumaceus (35.3 and 3.4%), respectively. The total digestible nutrients (TDN) ranged from 57.1% in Blepharis linariifolia to 69.3% in Tribulus terrestris with highest digestible energy (DE) in later while the lowest DE was obtained in Commelina spp (2.4%). The calculated in vitro organic matter digestibility (IVOMD) was highest for the Canavalia ensiformis (50.27%) and lowest value (43.17%) for Commelina spp. Zornia diphylla, Tribulus terrestris and Sesamum alatum showed highest nutritive value, while Alysicarpus glumaceus, Oldenlandia senegalensis and Chrozophora brocchiana showed highest palatability. It is concluded that these rangeland forbs are palatable and their CP and energy contents are sufficient to support different classes of livestock in South Darfur, Sudan.
文摘Annual growth rings of roots in perennial forbs have been used in studies of climate change and the ecology of grasslands. However, little has been done in this aspect of research in China. In this study, we report the characteristics of growth rings in the main roots of 13 herb species sampled in Duolun of the Inner Mongolia grassland in northern China. The results show that around two thirds of the species possess clearly demarcated annual rings in the root xylem. Some species of the same genera show different patterns in anatomical structure of the root xylem. Standardized annual ring widths of three species, Potentilla anserine L., Cymbaria dahurica L. and Lespedeza daurica (Laxm.) Schindh, show a common linear trend, indicating a continued favorable growth condition in the sampling sites. Our results provide evidence that growth rings in roots of some perennial forbs in the Inner Mongolia grassland can serve as a new and useful indicator of past changes in the grassland environment.
基金supported by the ANPCyT under grant PICT 2014-0865CONICET and Universidad Nacional del Sur from Argentina
文摘Fire is a natural disturbance occurring every few years in many grasslands ecosystems. However, since European colonization, fire has been highly reduced or even suppressed in Argentinean grasslands, fostering ignitable material accumulation. This has led to occasional catastrophic controldemanding fire events, extended for larger areas. The aims of this work are to study vegetation recovery and change after a non-natural fire event in mountain grasslands. The study area is located in the Ventania mountain system, mid-eastern Argentina. We studied vegetation recovery after fire(January 2014) in two different communities: grass-steppes(grasslands) and shrub-steppes(open low shrublands). We measured vegetation cover, species richness and bare ground percentage in burned and unburned areas 1, 4, 8, 11 and 23 months after fire. Vegetation surveys were also performed at the end of the growing season(December) 11 and 23 months after fire. Data were analyzed using regression analysis, ANOVA and multivariate analysis(NMS, PERMANOVA). Both communities increased their vegetation cover at the same rate, without differences between burned and unburned areas after two years. Species richness was higher in shrublands and their recovery was alsofaster than in grasslands. Considering functional composition, besides transient changes during the first year after fire, there were no differences in abundance of different functional vegetation groups two years after fire. At the same time, shrublands showed no differences in species composition, while grasslands had a different species composition in burned and unburned plots. Also, burned grassland showed a higher species richness than unburned grassland. Data shown mountain vegetation in Pampas grassland is adapted to fire, recovering cover and richness rapidly after fire and thus reducing soil erosion risks. Vegetation in mountain Pampas seems to be well adapted to fire, but in grasslands species composition has changed due to fire. Nonetheless, these changes seem to be not permanent since prefire species are still present in the area.
文摘福布斯最新发布的"亚洲地区30位30岁以下领袖榜"(Forbes 30 Under 30 Asia)中,来自上海热巢网络科技有限公司(下称"热巢")的两位创始人——穆青与他的德国小伙伴Fabian von Heimburg当选广告与传媒领域青年领袖。对穆青来说,这份荣誉来得并不突然。早在2016年10月,德国总理默克尔访华期间与李克强总理共同讨论德国工业4.0和中国制造2025时,热巢作为唯一中德创新创业企业被邀请参加。这让穆青引以为豪。
文摘在《福布斯》杂志(Forbes)公布的2011年美国大学排行榜中,有三所美国军事院校名列前二十,其中名列第三的是西点军校(United States Military Academy,即美国军校),排名比哈佛大学还要高(名列第六);紧随在名列第九的麻省理工学院之后的是排名第十的美国空军军校(United States Air Force Academy);