14,500 years of vegetation and land use history in the upper continental montane zone at Lac de Champex (Valais, Switzerland)

Forests in the upper continental montane zone are important ecotones between lowland and subalpine forest ecosystems. A thorough understanding of the past vegetation dynamics at mid elevation is crucial to assess past and future altitudinal range shifts of tree species in response to climate change. Lake sediments from Lac de Champex (1,467 m a.s.l.), a small lake in the Canton Valais in the Central Swiss Alps were analysed to reconstruct the vegetation, land use and fire history for the last 14,500 years, using pollen, macrofossils, non-pollen palynomorphs and charcoal. The record indicates that the tree line had already reached the Champex area during the Allerød (14,000 cal bp) but dropped below the lake’s catchment during the Younger Dryas cooling (12,750–11,550 cal bp). Reforestation started again with Betula and Pinus sylvestris in the Early Holocene at 11,500 cal bp in response to rapid climate warming. Temperate tree species (Ulmus, Tilia, Quercus, Acer) may have reached the altitude of the lake during the Holocene Thermal Maximum (ca. 10,000–5,000 cal bp). Mixed forests with mesophilous Abies alba were dominant between 7,500 and 5,000 cal bp. The mass expansions of Picea abies after 5,000 cal bp and Alnus viridis thickets after 4,500 cal bp were directly linked to increasing human disturbance. High values of coprophilous Sporormiella fungal spores and cereal pollen suggest pastoral and arable farming at the site from the Late Neolithic/Early Bronze Age onwards (5,000 cal bp). Our data imply that vegetation at intermediate elevation was less affected by human activities than at higher or lower elevations but that these areas served as important stations between the permanent settlements in the valleys and the seasonally occupied alpine huts at higher elevations. We argue that future climate warming will lead to drastic reorganizations of mountain ecosystems.

Planetary Layer Lapse Rate Comparison of Tropical,Montane and hot Semi-Arid Climates of Nigeria

This study assessed the pattern of planetary layer lapse rate across the major climate belts of Nigeria. Six years’ data (2010-2015) for air temperature values between 1000 mbar and 850 mbar atmospheric pressure levels were acquired from Era-Interim Re-analysis data centre. The data was retrieved at 6-hourly synoptic hours: 0000H, 0600H, 1200H and 1800H at 0.125o grid resolution. Results showed that the lower tropospheric layers throughout the various climate belts has a positive lapse rate. Findings also revealed that the average annual lapse rate condition were: Tropical wet zone (Port Harcourt) -5.6 oC/km; Bi-modal Tropical continental zone (Enugu) 5.8 oC/km; Montane zone (Jos) -6.5 oC/km; Mono-modal Tropical continental zone (Kano) -6.6 oC/km; and Hot semi-arid zone (Maiduguri) -6.6 oC/km. This average values presents the lapse rates to be close to the Saturated Adiabatic Lapse Rate (SALR). Average diurnal results for the climate belts showed that lapse rate is higher during the afternoon and transition periods than the rest periods and increases from the coastal areas northward. The seasonal periods of highest lapse rates during the day time are from December – May (i.e. 5.8-9.5 oC/km) with slight decrease from June – November. The positive lapse rate of range -1.8 – -5.9 oC/km observed during the period of dawn across the entire region showed that infrared radiation was still being released and modified by less energetic mechanical turbulence that characterizes the surface layer across Nigeria. This also indicates that global warming is real and in substantial effect. The study findings imply that conditional instability prevailed over the entire region, therefore, the planetary layer environment will be of slow to moderate dispersive potential and will require forceful mechanism to lift emissions are introduced into it. It is recommended that industrial stacks are above 50 m to enhance the dispersion of emissions aloft.

Growth and Yield Performance of French Bean (Phaseolus vulgaris L.) Germplasm under Sub-Montane Zone of Maharashtra

The present investigation was undertaken in randomized block design with two replications during rabi-2018 at Instructional-cum-Research Farm, RCSM College of Agriculture, Kolhapur. A set of 15 germplasm of French bean viz. Phule Suyash, Phule Surekha, Contender, Sevil, Arka Suvidha, Arka Komal, IC -039081, IC -28008, EC -28304, EC -500354, EC -500377, Selection -9, Falguni, Vaishnavi and EC -530909 was evaluated. The data indicated the significant differences with respect to growth and yield among the various germplasm of french bean. The earliest 50% flowering was seen in Contender (33.13 days) whereas the maximum number of days required for 50% flowering was in IC- 0339081 (45.60 days) closely followed by Falguni (42.20). As far as the numbers of primary branches per plant, Arka Suvidha had 2.70 at 30 DAS and 3.80 at 45 DAS while the germplasm IC-28008 recorded the highest number of secondary branches per plant (6.80 and 8.60) at 45 and 60 DAS, respectively. The tallest plants were observed in Phule Surekha (22.90 cm) at 30 DAS while at 45 and 60 DAS, taller plants were noticed in IC-28008 (78.70 and 93.75cm, respectively). The number of pod cluster per plant was found to range from 28.60 (EC-28304) to 12.00 (Selection-9). The highest pod length and width were noticed in Selection -9 and Phule Surekha (14.29 cm and 1.51cm, respectively) whereas the least pod length was found in Phule Surekha and Vaishnavi (9.21cm and 0.69cm, respectively). The highest number of pods per plant (162.40), individual pod weight (3.85g) and number of seeds per pod (7.60) were higher in EC -500354 which resulted in higher yield per hectare (34.73 t) followed by Arka Komal (24.22 t) and Phule Surekha (21.42 t.).