The reflection method of line intercept sampling to eliminate boundary bias

1994 ◽  
Vol 1 (3) ◽  
pp. 219-226 ◽  
Author(s):  
Timothy G. Gregoire ◽  
Nicholas S. Monkevich
2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Ruslan A. Gopar ◽  
S. Martono ◽  
Muhamad N. Rofiq ◽  
Windu N.

The objective of this experiment was to obtain forage/ cover crops productivity and carrying capacity for ruminant animals in Pelalawan Regency, Riau in the dry season. Data were collected from civil palm oil plantations at the aged 7, 10 and 14 years in the end of dry season with a destructive sampling method. Sampling used line intercept method which every hectare were picked 10 points by using a pair of 1 m2 sized quadrant. The result showed that the number of vegetations/ cover crops in oil palm plantations aged 7, 10 and 14 years was 42 types.The proportion of forage which consist grass, legume and ferns was diverse at each age of oil palm plantations. Forage production under oil palm plantations aged 7, 10 and 14 years were 2,571 kg/ha, 1479.76 kg/ha and 1417.22 kg/ha as fed and amounted to 811.41 kg/ ha, 471, 15 kg/ ha and 456.91 kg/ ha in the dry matter production. Average carrying capacities of oil palm plantations aged 7, 10 and 14 years was 0.36 Animal units (AU)/ha/year, 0.21 AU/ha/year and 0.20 AU/ ha/year.Penelitian ini bertujuan untuk mengetahui potensi jumlah covercrop dan kapasitas tampungnya di kebun sawit sebagai sumber pakan hijauan ruminansia pada musim kemarau di kabupaten Pelalawan, Riau. Pengambilan data dilakukan di perkebunan kelapa sawit yang berumur 7, 10 dan 14 tahun milik rakyat pada akhir musim kemarau. Pengambilan sampel dengan destructive sampling method menggunakan metode garis berpetak memakai kuadran berukuran 1m2 dengan jumlah sampel tiap area sebanyak 10 titik. Berdasar hasil pengukuran diperoleh hasil jumlah vegetasi/ covercrop yang ada di kebun sawit berumur 7, 10 dan 14 tahun sebanyak 42 jenis yang bervariasi tiap umur tanaman sawit. Proporsi hijauan yang ada meliputi jenis rumput, legume dan paku-pakuan bervariasi pada tiap umur kebun sawit. Produksi hijauan yang ada di bawah kebun sawit berumur 7, 10 dan 14 tahun berturut-turut 2.571 kg/ha, 1.479,76 kg/ha dan 1.417,22 kg/ha dalam bentuk segar serta sebesar 811,41 kg/ha, 471,15 kg/ha dan 456,91 kg/ha dalam bahan kering. Kapasitas tampung dari kebun sawit berumur 7, 10 dan 14 tahun adalah 0,36 satuan ternak (ST)/ha, 0,21 ST/ha dan 0,20 ST/ha.Keywords: cover crops, oil palm plantation, forage, ruminant, dry season, Pelalawan


Hydrobiologia ◽  
2021 ◽  
Author(s):  
L. Saponari ◽  
I. Dehnert ◽  
P. Galli ◽  
S. Montano

AbstractCorallivory causes considerable damage to coral reefs and can exacerbate other disturbances. Among coral predators, Drupella spp. are considered as delayer of coral recovery in the Republic of Maldives, although little information is available on their ecology. Thus, we aimed to assess their population structure, feeding behaviour and spatial distribution around 2 years after a coral bleaching event in 2016. Biological and environmental data were collected using belt and line intercept transects in six shallow reefs in Maldives. The snails occurred in aggregations with a maximum of 62 individuals and exhibited a preference for branching corals. Yet, the gastropods showed a high plasticity in adapting feeding preferences to prey availability. Drupella spp. were homogenously distributed in the study area with an average of 9.04 ± 19.72 ind/200 m2. However, their occurrence was significantly different at the reef scale with the highest densities found in locations with higher coral cover. The impact of Drupella spp. appeared to be minimal with the population suffering from the loss of coral cover. We suggest that monitoring programs collect temporal- and spatial-scale data on non-outbreaking populations or non-aggregating populations to understand the dynamics of predation related to the co-occurrence of anthropogenic and natural impacts.


1995 ◽  
Vol 5 (1) ◽  
pp. 3-5 ◽  
Author(s):  
Kwang-Hyun Baek ◽  
He-Young Sung ◽  
Wee Sang Park
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document