Sustainable Agriculture and Food: Four volume set (Earthscan Reference Collections)

Integrated Farming Systems at Different Scales 467

and soil erosion has become a prosperous and green county (Li et al, 1994). Field
observations from watershed management show that protective forests have good
effects on water conservation, while improving soil structure and chemical proper-
ties (Tang and Guo, 1995; Xiang, 1996). In addition, the crown and understorey
layer of protective forest are capable of intercepting precipitation, reducing flow
speed of surface run-off, increasing soil penetrability and enhancing water and soil
conserving capacity. The protective forests have played a key role in maintaining
soil fertility and conserving water and soil.

Table 18.19 (continued)

Species Single-storied forest Multi-storied forest

D (m) Stems/ha D (m) Stems/ha

Ligustrum

lucidum

3 × 4–3 × 3 1665–4440

Phyllostamus

pubescens

7 × 7–5 × 5 495–825 4 × 5–4 × 4

Sinocalamus

affinis

4 × 4–3 × 3 825–1110 495–615

Juglans regia 4 × 5–3 × 3 195–390 6 × 6–4 × 5

Aleurites fordii 8 × 6–6 × 7 615–1110 7 × 8–5 × 6 270–495

Castanea

mollissima

6 × 7–5 × 6 495–825 10 × 10–8 × 9 180–330

Litchi chinensis 3 × 4–2.5 × 3 150–240 9 × 9–6 × 7 90–135

Euphorbia lorgan 1.5 × 1.5–0.8 × 0.8 240–330 4 × 5–3 × 4 120–240

Citrus reticulata 2 × 3–1.5 × 2 825–1335 2 × 3–1 × 2 495–825

Morus alba 2 × 2–1 × 1.5 440–15,630 4 × 5–3 × 3 1665–4995

Fraxinus

chinensis

6 × 7–4 × 5 1665–3330 495–825

Trachycarpus

fortunei

3 × 4–2 × 3 2205–6660

Rhus pyrifolia l × 1–0.5 × 0.5 204–495

Camellia oleifera 1.5 × 1.5–1 × 1 825–1665

Coriaria sinica,

Maxim

2 × 2–1 × 1 10,005–19,995

Amorpha fruticosa1 × 1.5–0.8 × 1 4440–10,005

Nerinus indicum 1 × 1–0.7 × 1 825–2130

Rosa roxburghii 1 × 1–0.5 × 0.5 6660–13,245

Miscanthus

sinensis

10,005–14,280

Saccharum

spowtaneum

10,005–40,020