intTypePromotion=1
zunia.vn Tuyển sinh 2024 dành cho Gen-Z zunia.vn zunia.vn
ADSENSE

Báo cáo lâm nghiệp: " production in an irrigation and tilization field experiment with Eucalyptus globulus Aboveground biomas"

Chia sẻ: Nguyễn Minh Thắng | Ngày: | Loại File: PDF | Số trang:3

53
lượt xem
5
download
 
  Download Vui lòng tải xuống để xem tài liệu đầy đủ

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: production in an irrigation and tilization field experiment with Eucalyptus globulus Aboveground biomass...

Chủ đề:
Lưu

Nội dung Text: Báo cáo lâm nghiệp: " production in an irrigation and tilization field experiment with Eucalyptus globulus Aboveground biomas"

  1. fer- production in an irrigation and biomass Aboveground tilization field experiment with Eucalyptus globulus 3 Flower-Ellis 1 L. Leal M. Tomé C. Araújo J.S. Pereira 2 J. 1 3ricsson T. Ericsso 1 CELBI (Cellulose Beira Industrial), Figueira da Foz, Portugal, 2 I’ortugal, and Instituto Superior de Agronomia, Dept of Forestry, P-1399 Lisbon, 3 Swedish University of Agriculture Sciences, Uppsala, Sweden 32 P plus micronutrients. Fertilizers containing Introduction 90 kg/ha and 1 kg/ha of N were applied in 0 6 1986 and 1987, respectively. 2) I - water sup- For a given climate, optimal growth rates plied daily from April through October, through may be achieved if mineral nutrient addi- drip tubes. In 1986 and 1987, 611 and 629 mm of water were supplied by irrigation in addition tions are scheduled to meet the needs of to 645 and 905 rnm of rainfall in 1986 and 1987, the plants determined by their relative respectively. 3) IL irrigation as in I plus a - growth rate (Ingestad, 1988). To assess complete liquid fertilizer, with micronutrients, optimum biomass production of Eucalyp- applied once per week according to the needs of the plants estimated by the relative growth tus globulus in Portugal and to study the rate. The total fertilizer supplied was, in kg/ha, physiological mechanisms of the response 60 N, 46 K and :?6 P in 1986 and 160 N, 123 K to the addition of nutrients and water, a and 69 P in 1987. Each treatment was applied field experiment was established in March to 2 plots with an area of 0.30 ha each, leaving 1986 (Pereira et al., 1988). In this paper, 2 protection rows between plots. Twelve trees per treatment were harvested we present the results of aboveground for biomass studies in September of 1986 and biomass production and partitioning for February of 1987. In February of 1988, 10 trees the 1 st 2 yr of growth. per treatment were selected for the same pur- pose. Biomass components were separated and a subsample of each component was oven- dried at 80°C to evaluate the dry weight to fresh Materials and Methods weight ratio and estimate biomass. Planting took place in March of 1986 at a spac- ing of 3 x 3 m. At planting, each seedling re- Results ceived 200 g of NPK fertilizer containing 14 g N, 18.3 g P and 11.6 g K. The experimental design consisted of 3 treatments and a rainfed control As shown in Table I, the treatments (C). 1) F solid fertilization applied twice per - strongly affected growth especially in the growing season (in spring and autumn) to rain- irrigated treatments (IL and I). During the fed plots. The fertilization consisted of a broad- first 6 mo, the effect of F was negligible, cast fertilizer, with the proportions 100 N: 88 K:
  2. compared to the control (C), whereas, as in IL and I, the aboveground biomass was 262 and 185% greater than in C. That was a period when water stress occurred in the rainfed plots (F and C). During the following rainy season (September 1986- February 1987) and during the 2nd yr of growth, there was a significant increase in the biomass of the F plots. In all cases, IL andI resulted in higher biomass accumu- lation rates than the rainfed treatments. The annual biomass production accumul- ated during the period until canopy closure was linearly related to the leaf area index LAI (Fig. 1). The fastest growing trees (IL) had reached a high LAI by February 1988 (LAI 4.1The proportion of each bio- = mass component changed with treatments (Table II). Leaves represented a greater percentage of total biomass in the rainfed (F and C) than in IL and I. The treatments accumulation of stem biomass was greater in IL andI than in F and C, both in absolute amounts and in relation to the amount of foliage biomass (see Table II). Most of the variation in stem biomass resulted from wood accumulation, since bark varied only between 6 and 9%, effect on biomass production in compari- approximately. son with irrigation or fertilization alone, as had been suggested by Ingestad (1988). An abundant water supply in the summer Discussion (I) ranked second in promoting biomass accumulation, suggesting that water defi- The supply of water and mineral nutrients cits play a major role in decreasing pro- according to plant needs had the greatest duction under these climatic conditions.
  3. One of the major effects of the treatments References to increase leaf production in relation was to the control and biomass production was Cannell M.G.R. (1985) Dry matter partitioning in strictly related to LAI until canopy closure. tree crops. In: Trees as Crop Plants. (Cannell M.G.R. & Jackson J.E., eds.), Institute for Ter- The photosynthetic capacity of each indivi- restrial Ecology, Monks Wood, Huntingdon, dual leaf did not increase significantly with U.K. pp. 160-193 fertilization and irrigation (unpublished Ingestad T. (I ) New concepts on soil fertility 8 9E ! data). This also suggests that models and plant nutrition as illustrated by research on based upon a simple relationship between forest trees and stands. Geoderma 40, 237-252 biomass production and light interception McMurtrie R.E., Landsberg J.J. & Linder S. by the foliage (a function of LAI ) may be (1989) Research priorities in field experiments on fast-growing tree plantations: implications of applied over a range of environmental a mathematical production model. In: Biomass situations for young eucalypt plantations Production by Fast-Growing Trees. (Pereira (McMurtrie et al., 1988). Irrigation alone or J.S. & Landsberg J.J., eds.), Kluwer, Dordrecht, with fertilization resulted in larger plants pp. 181-207 with a greater percentage of stem in rela- Pereira J.S., Linder S., Araujo M.C., Pereira H., Ericsson T., Borralho N. & Leal L. (1988) Opti- tion to total and foliage biomass than in mization of biomass production in Eucalyptus the rainfed plots. It is likely that, in the a case study. In: Bio- globulus plantations - absence of irrigation, more biomass was mass Production by Fast-Growing Trees. (Per- allocated to roots than to stem, as sug- eira J.S. & Landsberg J.J., eds.), Kluwer, Dor- gested by Cannell (1985). drecht pp. 101-121
ADSENSE

CÓ THỂ BẠN MUỐN DOWNLOAD

 

Đồng bộ tài khoản
2=>2