III. Vertical distribution at eleven sites

Abstract

Soil samples from 0--2. 5,[10][11][12][13][14][15][16][17][18][19][20][20][21][22][23][24][25][26][27][28][29][30] Oturoa, Rotoiti, Stratford, Egmont, Tokomaru, Kokotau, Kaitoke, Otiake, Edendale, and Waikiwi soils were collected in spring and total nematode populations found to be I 097 {)()()-9 595 OOO/m 2 • Over the II sites vertical distribution at the 6 depths (46, 24, II, 7, 9, 3% in successive strata) was most significantly correlated with soil carbon and readily available soil phosphorus. It is considered the causal correlation of nematodes is with root growth. Correlations with soil physical factors are given. A total of37 genera were identified, 14-20 being found at each site. Mean number ofgenera in the strata sampled was 14,13,12,9,10,6. The greatest diversity of genera occurred in Oturoa sand, a soil derived from a 9O-yearold volcanic ash shower. Populations for each genus, depth, and site are given.Complementary distributions found include Aphelenchoides/Aphelenchus, Heterocephalobus/Cephalobus, Anaplectus/Plectus, Monhystera + Chromadoridae/ Rhabditidae + Plectidae. Tylenchida and Dorylaimida also appear to be complementary; the large biomass of the Dorylaimida populations suggests many of them may be directly dependent on plants for food, as are Tylenchida.

Cover crops in pear (Pyrus communis) orchards: effects on soil nematode assemblage

“…This differential distribution pattern applies to both inter-rows and rows alike. Previous studies have shown a similar trend (31,39). Total nematode abundance was generally greater in inter-rows than in rows at a depth of 0-20 cm (table 2, page 90).…”

“…Plant functional type regulates the vertical distribution of soil organic carbon (19). Root system morphology controls the availability of soil organic carbon and phosphorus (31,39) and the vertical distribution of nematodes in the soil (33). Soil fauna depends on carbon resources through the complex interactions between the roots and microorganisms (5).…”

Penggunaan lahan dan deforestasi di Kabupaten Bogor

“…Untuk mengetahui jenis penggunaan lahan serta aktivitas pada wilayah tersebut, maka dapat diketahui komponen -komponen pembentukan lahan (Kaiser et al, 1995). Menurut Yeates (1980), komponen penggunaan lahan suatu wilayah terdiri atas:…”