Tag: plants
New approaches for delineating n-dimensional hypervolumes
Guidelines to Produce Quality Planting Material of Agroforestry Species
Agroforestry—an effective, traditional land management system of integrating trees and shrubs into various crops and croplivestock production systems—has been practiced in India for centuries. Covered under the umbrella of agriculture before, it was only recently that agroforestry emerged as a distinct branch of science. The past three decades have witnessed a tremendous boost to agroforestry across the world, and India is among those pioneer countries which are taking major actions to step up the research, education, and policy level support to agroforestry.
Agroforestry and the development of tropical forestry
This paper is divided into three parts. Part one deals specifically with deforestation. Deforestation is caused mainly by 1) conversion of forest lands into agricultural lands, 2) the quest for fuelwood and building poles, and 3) social and economic deprivation. The author warns of the dangers of confusing symptoms with cause of deforestation. Before embarking on the subject of agroforestry, the author, in the second part of this paper, gives a broad view of the ecological requirements of various plant species. The final, well detailed and comprehensive section deals specifically with agroforestry related aspects. A list of suitable agroforestry trees, shrubs and fodder crops is included.
Relating plant diversity to biomass and soil erosion in a cultivated landscape of the eastern seaboard of Thailand
Plant diversity can affect ecological processes through effects on biomass and soil condition. A study was carried out in an agricultural watershed of Thailand to document plant species richness of different agricultural land uses and to assess its relationship with biomass and soil erosion. A nested sampling design of 20 x 20 m, 10 x 10 m, 5 x 5 m and 1 x 1 m quadrats was employed to study species richness of three categories of plants: herbaceous plants, shrubs and trees. Interviews were conducted with farmers who owned the cultivated fields where sampling plots were located. Plant diversity was assessed by computing Shannon index, Simpson index, and Species richness. Species utility index, which is the percentage of species identified as useful, was also estimated for each land use. Biomass was estimated using methodology recommended by FAO and soil erosionwas estimated using the universal soil loss equation (USLE). From among the different land use types, mixed orchard ranked first in terms of plant diversity while paddy ranked last. Land uses with monocropping of shrubs, such as cassava, pineapple and sugarcane had lower plant diversity than land uses with monocropping of trees, such as coconut and para rubber. Monocropping of eucalyptus was an exception. Rotations of monocrops, namely pineapplecassava and sugarcanecassava, or intercropping, namely coconutcassava, also had a higher plant diversity as compared to monocropping of shrubs. The highest species utility index of 61 was found in orchards, the lowest of 9 was found in Eucalyptus plantations. Plant diversity was found to have a significant positive correlation with biomass and a negative, though non-significant, correlation with soil erosion.
Kaliyandra: okutandika n’okulabirira nasale
Kaliyandra (Caliandra calothyrsus) kati katono nga kamulisa ebimuli imyufu. Kakula bulungi mubulimbeera z’obudde, kumbalama zenyanja, kunsozi, naye kasinga kukola bulungi mubifo omulimibwa emwanyi. Ettaka eritaddako mmere, ebifo amazzi mwegakunganilra, n’obunyogovu Obungi bukosa okukula kwa Kaliyandra. Akati Kano kakula mangu nnyo era otandika okuganyulwa mumuti guno mubbanga Iya mwaka ggumu nga kamaze okusimbibwa. Omuti guno gusobola okuvaako emmere yebisolo okussuka emyaka kumi. Omuti guno gusobola okusimbibwa awantu wonna munimiro/ faamu engeri gyegutavuganya nabimera birala ebigulirannaye, kasita guba nga gulabiriddwa bulungi okukendeeza kukisikirize kyaagwo okubikka ebimera ebirala.
African plum: Dacryodes edulis
BOTANIC DESCRIPTIONDacryodes edulis is a medium-sized, evergreen tree attaining a height of 18-40 m in the forest but not exceeding 12 m in plantations. It is generally branched from low down, with a deep, dense crown. The bole is rather short, slightly fluted, 50-170 cm in diameter and more or less sinuous. The scented, pale grey, rough bark exudes a whitish resin. Buttresses are absent.Leaves compound, imparipinnate, with 5-8 pairs of leaflets; glossy above, pubescent, the pubescence disappearing with age.Flowers subtended, 3 lobed, conspicuous, caducous brow bracts, fragrant, about 5 mm across, trimerous except for the ovary, arranged in dense, ferruginous, stellate-tomentose inflorescence; sepals 3, brown; petals 3, cream-yellow; stamens 6, white; disc 6 lobed, surrounding the 2-celled, glabrous ovary; inflorescence axis 10-42 cm long or longer, deeply grooved.Fruits ellipsoidal drupes rather variable in size, 4-12 x 3-6 cm, resembling olives; exocarp thin, pink, becoming dark blue to violet at maturity; pulp firm and thin.
Annual litter fall of nitrogen-fixing tree species in rotational woodlots at Tumbi (Tabora), western Tanzania
A rotational woodlot is a method involving growing trees with crops up to 2-3 years until trees start competing with crops. Thereafter the woodlot is left as a source of fuel wood, building poles or fodder while restoring soil fertility until farmers start cutting down the trees and growing crops between the stumps 4 to 5 years later. The method was designed and developed by the South African Development Countries (SADC) and the World Agroforestry Centre(ICRAF) and their partners to alleviate rural farmers from the problems of fuelwood scarcity and poor soil fertility in the tobacco cereal land use system. The method is currently being practised at farmers’ fields in Tabora rural district in western Tanzania involving a large number of farmers. This study reports an assessment of litter production and seasonal pattern of Acacia crassicarpa , A. julifera , A. leptocarpa, Leucaena pallida and Senna siamea grown in rotational woodlots at five years of age.
Do species mixtures increase above- and belowground resource capture in woody and herbaceous tropical legumes?
The rotation of crops with planted, N2-fixing legumes is a promising agroforestry innovation for replenishing soil fertility in the tropics. We postulated that woody and herbaceous legumes with different growth and rooting patterns could be mixed to optimize above- and belowground resource capture. The objective of this study was to evaluate the effect of species interactions on resource utilization by legumes grown in mixtures on a Kandiudalfic Eutrudox in western Kenya. Four woody legume shrubs—pigeonpea [Cajanus cajan (L.) Millsp.], sesbania [Sesbania sesban (L.) Merr.], crotalaria (Crotalaria grahamiana Wight and Arn.), and tephrosia (Tephrosia vogelii Hook F.)—grown in monoculture and mixed stands were evaluated for light interception, soil N and water uptake, and biomass production. Siratro [Macroptilium atropurpureum (DC.) Urb.] and groundnut (Arachis hypogaea L.) were undersown in woody legume stands. Total aboveground biomass production ranged from 9 to 13 Mg ha1 for monoculture and 8 to 15 Mg ha1 for mixtures of woody legumes. Total N in woody-legume stands ranged from 100 to 178 kg N ha1 Biomass and plant N were not significantly different among woody-legume treatments. However, undersowing siratro as a supplement increased stand productivity and recycled biomass N. Species complementarity in topsoil and subsoil utilization of mineral N was observed in crotalaria + sesbania and pigeonpea + tephrosia mixed stands. Dense soil cover created by siratro led to better conservation of soil water. Results indicated that the tested mixtures provide a better risk management strategy through compensatory growth potential. Greatest opportunities for intensifying resource utilization appear to exist through undersowing a creeping legume with an open-canopy woody legume.
The relationship of Sophora sect. Edwardsia (Fabaceae) to Sophora tomentosa, the type species of the genus Sophora, observed from DNA sequence data and morphological characters
The genus Sophora and tribe Sophoreae to which it belongs have long been considered an unnatural assemblage in the Fabaceae. Tribe Sophoreae has been used as a group of convenience for species that are characterized by relatively simple flowers with free stamens and unspecialized pinnate leaves. In regard to taxonomic problems in Sophora , Salisbury (1808: 296) made the following comments: ‘There is no genus in the vast natural order of Leguminosae, which appears to me so great a disgrace to modern botanists, as Sophora . . . Sophora, as it stands in the last edition of Systema Vegetabilium , contains at least eight genera, very few if any of which will follow each other, in a natural series . . . It is well known that our great master Linne only regarded Sophora as a reservoir, into which he put every leguminous plant with distinct stamina, that he could not refer to any other established genus.