糙毛假地豆(Desmodium heterocarpum DC var. strigosum Van Meeuwen)是多年生豆科草本植物,在广东省郁南县自然条件下零星分布,未形成大面积种群。研究表明,该植物适应光照能力强,适于荫蔽林下生长;其叶片冬季具有较高的叶绿素含量及...糙毛假地豆(Desmodium heterocarpum DC var. strigosum Van Meeuwen)是多年生豆科草本植物,在广东省郁南县自然条件下零星分布,未形成大面积种群。研究表明,该植物适应光照能力强,适于荫蔽林下生长;其叶片冬季具有较高的叶绿素含量及一定的净光合能力,且根部仍具有固N活性根瘤;根系发达,地上部分形成密实覆盖层,与其他杂草竞争能力强,具有多种生态功能,在开发利用当地生物资源中具有较高的应用价值。展开更多
Field experiments were conducted at Dabagi Farm of the Usmanu Danfodiyo University, Sokoto （13~I＇N and 5~15＇ E）, in the Semi-arid of Nigeria, during 2007 and 2008 rainy seasons to determine the effect of sowing me...Field experiments were conducted at Dabagi Farm of the Usmanu Danfodiyo University, Sokoto （13~I＇N and 5~15＇ E）, in the Semi-arid of Nigeria, during 2007 and 2008 rainy seasons to determine the effect of sowing methods on growth and fodder yield of Stylosanthes hamata cv. Verano. Three sowing methods （dibbling, broadcasting and drilling） were investigated. The experimental design adopted for the study was the randomized complete block design （RCBD） replicated three times. The parameters monitored included plant height （cm）, leaf length （cm）, leaf width （cm）, number of leaves, canopy spread （cm）, stand count and herbage yield. Samples were randomly taken and marked for the measurement of the parameters at 2, 4, 6, 8, 10, 12 and 14 weeks after sowing （WAS）. Herbage yield （kg hal） was determined at the end of the 14th week. Result of the study revealed that the sowing methods had significant effect （P 〈 0.05） on growth parameters at 2 to 14 WAS in 2007, 2008 and in their combined analysis. Dry matter yield differed （P 〈 0.05） significantly. Dibbling method produced plants that were taller, longer, with wider canopy spread and leaves as well as more leaves and stands （P 〈 0.05）. The year 2007 produced taller plants, longer, wider canopy spread and leaves as well as more leaves and stands （P 〈 0.05） in all the weeks compared to the year 2008. It was therefore concluded from the results of this study that dibbling method of sowing was the best for Stylosanthes hamata cv. Verano production at 50 ~ 50 cm inter and intra-row spacing in the semi-arid of Sokoto agro-ecology in northwestern Nigeria, presumably due to low competition for scarce moisture and creation of more space in this sowing method.展开更多
Amino compounds （ACs）, i.e., amino acids and amino sugars, are the major forms of organic nitrogen （N） in animal manure and soil. To increase our understanding on the effect of long-term poultry litter （PL） appl...Amino compounds （ACs）, i.e., amino acids and amino sugars, are the major forms of organic nitrogen （N） in animal manure and soil. To increase our understanding on the effect of long-term poultry litter （PL） application on soil AC pools and turnover, in this study, we determined the contents of 21 ACs in 23 PL samples, i5 soil samples collected from 0-20, 20-40, and 40-60 cm layers of five pasture plots with 0, 5, 10, 15 and 20 years of PL applications, and 5 grass shoot samples grown on these pasture fields. The contents of 21 ACs were simultaneously determined by methanesulfonic acid hydrolysis/extraction and anion chromatography-pulsed amperometry. PL application increased soil total and individual AC contents with a distribution pattern similar to that of AC in PL. The highest AC-N concentrations were observed in the soils with 10- or 15-year PL applications, inconsistent with the order of annual application rates or eunmlative applied PL amounts. Application of PL increased the AC contents in grass shoots whereby the highest increase of most ACs was with the shoots from the fields that received PL for 5 years. These observations suggested that both freshly applied and residual PL had contributions to the soil AC-N, and that PL application also accelerated AC-N transformation in soil.展开更多
Crop-livestock integration(CLI)is a significant practice for livestock grazing systems in alpine rangelands.It offers the potential to achieve sustainable crop and livestock production.However,the separate crop and li...Crop-livestock integration(CLI)is a significant practice for livestock grazing systems in alpine rangelands.It offers the potential to achieve sustainable crop and livestock production.However,the separate crop and livestock systems that exist today have led to issues of intensive agriculture,rangeland degradation and forage shortage in the Tibetan Plateau.Developing crop-livestock integration through sown pastures can be an effective way to lift pasture productivity and improve livestock production.Thus,to explore the potential for integrating crop and livestock production in alpine grazing systems,an assessment of potential forage and livestock production using multiple datasets was carried out in Burang County,China.Results showed the marginal land potentially available for sown pastures was about 560 ha,located mostly in the Burang township of the Karnali basin.Accumulated temperature was the dominant limiting factor for establishing sown pastures,therefore cold tolerance of forage species and growth period should be taken into consideration.Furthermore,the number of livestock decreased during the period 2012–2016;yet often,the number of livestock in rangeland landscape was greater than that in agro-pastoral landscape.The average number of livestock was about 110000 standard sheep units(SU)in the study area,but forage from sown pastures and crop residues could potentially feed about 11000 SU,accounting for 50%of the livestock population in the Karnali basin.We found that integrating crop and forage production could fill feed gaps for grazing systems,particularly in the agro-pastoral landscape of the Karnali basin.The results of this study provide scientific support to guide future forage production and to promote further crop and livestock integration in Burang County.展开更多
文摘糙毛假地豆(Desmodium heterocarpum DC var. strigosum Van Meeuwen)是多年生豆科草本植物,在广东省郁南县自然条件下零星分布,未形成大面积种群。研究表明,该植物适应光照能力强,适于荫蔽林下生长;其叶片冬季具有较高的叶绿素含量及一定的净光合能力,且根部仍具有固N活性根瘤;根系发达,地上部分形成密实覆盖层,与其他杂草竞争能力强,具有多种生态功能,在开发利用当地生物资源中具有较高的应用价值。
文摘Field experiments were conducted at Dabagi Farm of the Usmanu Danfodiyo University, Sokoto （13~I＇N and 5~15＇ E）, in the Semi-arid of Nigeria, during 2007 and 2008 rainy seasons to determine the effect of sowing methods on growth and fodder yield of Stylosanthes hamata cv. Verano. Three sowing methods （dibbling, broadcasting and drilling） were investigated. The experimental design adopted for the study was the randomized complete block design （RCBD） replicated three times. The parameters monitored included plant height （cm）, leaf length （cm）, leaf width （cm）, number of leaves, canopy spread （cm）, stand count and herbage yield. Samples were randomly taken and marked for the measurement of the parameters at 2, 4, 6, 8, 10, 12 and 14 weeks after sowing （WAS）. Herbage yield （kg hal） was determined at the end of the 14th week. Result of the study revealed that the sowing methods had significant effect （P 〈 0.05） on growth parameters at 2 to 14 WAS in 2007, 2008 and in their combined analysis. Dry matter yield differed （P 〈 0.05） significantly. Dibbling method produced plants that were taller, longer, with wider canopy spread and leaves as well as more leaves and stands （P 〈 0.05）. The year 2007 produced taller plants, longer, wider canopy spread and leaves as well as more leaves and stands （P 〈 0.05） in all the weeks compared to the year 2008. It was therefore concluded from the results of this study that dibbling method of sowing was the best for Stylosanthes hamata cv. Verano production at 50 ~ 50 cm inter and intra-row spacing in the semi-arid of Sokoto agro-ecology in northwestern Nigeria, presumably due to low competition for scarce moisture and creation of more space in this sowing method.
文摘Amino compounds （ACs）, i.e., amino acids and amino sugars, are the major forms of organic nitrogen （N） in animal manure and soil. To increase our understanding on the effect of long-term poultry litter （PL） application on soil AC pools and turnover, in this study, we determined the contents of 21 ACs in 23 PL samples, i5 soil samples collected from 0-20, 20-40, and 40-60 cm layers of five pasture plots with 0, 5, 10, 15 and 20 years of PL applications, and 5 grass shoot samples grown on these pasture fields. The contents of 21 ACs were simultaneously determined by methanesulfonic acid hydrolysis/extraction and anion chromatography-pulsed amperometry. PL application increased soil total and individual AC contents with a distribution pattern similar to that of AC in PL. The highest AC-N concentrations were observed in the soils with 10- or 15-year PL applications, inconsistent with the order of annual application rates or eunmlative applied PL amounts. Application of PL increased the AC contents in grass shoots whereby the highest increase of most ACs was with the shoots from the fields that received PL for 5 years. These observations suggested that both freshly applied and residual PL had contributions to the soil AC-N, and that PL application also accelerated AC-N transformation in soil.
基金The National Key Research and Development Program of China(2016YFC0502001,2016YFC0501803)Kailash Sacred Landscape Conservation and Development Initiative from ICIMOD
文摘Crop-livestock integration(CLI)is a significant practice for livestock grazing systems in alpine rangelands.It offers the potential to achieve sustainable crop and livestock production.However,the separate crop and livestock systems that exist today have led to issues of intensive agriculture,rangeland degradation and forage shortage in the Tibetan Plateau.Developing crop-livestock integration through sown pastures can be an effective way to lift pasture productivity and improve livestock production.Thus,to explore the potential for integrating crop and livestock production in alpine grazing systems,an assessment of potential forage and livestock production using multiple datasets was carried out in Burang County,China.Results showed the marginal land potentially available for sown pastures was about 560 ha,located mostly in the Burang township of the Karnali basin.Accumulated temperature was the dominant limiting factor for establishing sown pastures,therefore cold tolerance of forage species and growth period should be taken into consideration.Furthermore,the number of livestock decreased during the period 2012–2016;yet often,the number of livestock in rangeland landscape was greater than that in agro-pastoral landscape.The average number of livestock was about 110000 standard sheep units(SU)in the study area,but forage from sown pastures and crop residues could potentially feed about 11000 SU,accounting for 50%of the livestock population in the Karnali basin.We found that integrating crop and forage production could fill feed gaps for grazing systems,particularly in the agro-pastoral landscape of the Karnali basin.The results of this study provide scientific support to guide future forage production and to promote further crop and livestock integration in Burang County.
