Undergrowth

About: Undergrowth is a research topic. Over the lifetime, 795 publications have been published within this topic receiving 11911 citations. The topic is also known as: understorey & underbrush.

Dynamics of Undergrowth and Its Application to Vegetation Control of Planted Chamaecyparis obtusa Endl. Forests with Special Reference to Mitigation of Surface Soil Loss.

Abstract: 林分密度管理をヒノキ人工林における土壌保全目的での下層植生管理に応用するために, 高知県下のヒノキ人工林に28の調査プロットを設け, 下層植生に対する強度間伐の影響と, 通常の管理下での下層植生の動態を調べた。強度間伐試験地では設定後2～3年間の収量比数 (Ry) の推移と2～3年後の植被率を調べた。通常施業試験地では設定時を0年次として, 0, 5, 10～13年次のRyと植被率を調べた。その際, 調査プロットの海抜高 (温量指数) に基づいて三つの温度域 (ウラジロ・コシダ域, カシ域, 落葉樹域) を区別し, 植被率を6段階評価した被度指数を土壌侵食抑制効果と光要求度の異なる六つの生活型 (ウラジロ・コシダ, 陽性草本, 林床草本・地表植物, 常緑木本, 落葉木本, ササ) のおのおのについて別個に求めた。強度間伐が被度指数に及ぼす影響は生活型によって異なった。また, 同じ生活型でも温度域によって異なる反応を示すものがあった。通常施業試験地では調査期間を前期 (0→5年次) と後期 (5→10～13年次) に分け, 期間ごとに求めた各生活型の被度指数の期間変化量 (dC) とRyの期間累積偏差 (ΣdRy×100) との関係を調べた。両者の関係には生活型間での差や, 温度域間での差が認められた。また, 生活型別の被度指数の合計値が40未満の林分 (貧植生型林分) と40以上の林分を区別すると, dC とΣdRy×100との関係が両林分間で異なっていた。以上の結果に基づいて, 生活型, 温度域, 貧植生型林分か否か, を区別してRy-植被率関係のデータを集積することにより, 下層植生管理を目的とした密度管理モデルの実用性が高められることを指摘した。

The Spatio-Temporal Variation of LAI of the Larix principis-rupprechtii Plantation Ecosystems at Diediegou of Liupan Mountains of Northwest China

Abstract: From the observation of 1eaf area index(LAI) of 7 Larix principis-rupprechtii plantation plots at 3 layers(tree canopy,shrubs and herbage) on the north slope in the vegetation period(May-Oct) of 2009,the change of LAI along slope position,the vertical composition of LAI and its seasonal variation were studied at the semi-arid watershed of Diediegou,which locates at Liupan Mountains of Northwest ChinaThe results showed: 1) The LAI of tree canopy decreased basically with rising slope position,from 152—295 at slope foot to 015—027 at slope top;the LAI of shrubs layer increased at first and then decreased with slope position,from 005—006 at slope foot to 073—101 at up-middle slope and 019—030 at slope top;while the LAI of herbage layer increased slowly,from 018—036 at slope foot to 019—075 at slope top2) The seasonal variation of LAI of tree canopy and herbage layers showed the same tendency,iea one-peak curve of increase and then decrease with timeHowever,the LAI of tree canopy layer grew faster than that of herbage layer in the early vegetation period(May-Jun) and slower than that of the herbage layer in the middle vegetation period(Jul–Aug),due to the integrated result of varying temperature and soil moisture as well as the root depth difference between trees and grasses3) With increasing tree canopy density,the LAI of each vegetation layer responded differentlyThe tree canopy LAI nearly linearly increased with canopy density;the LAI of shrubs layer increased at first and then decreased,with a maximum when the canopy density was about 05 and decreased to nearly zero when canopy density above 09;the LAI of herbage layer decreased gradually,from 074 to 035;the LAI of undergrowth(shrubs plus herbage) reached its maximum value and higher than tree canopy LAI when canopy density varied between 04—05,but decreased rapidly and lower than canopy LAI when canopy density above 06;the total LAI of all the 3 layers increased at first with rising canopy density,reaching its maximum and keeping relatively stable when canopy density was 06—08,and then slightly decreased with rising canopy density

Undergrowth cutter and subsoiler

Abstract: My invention relates to an undergrowth cutter and sub-soiler and has particular reference to a cutting tool adapted to cut the roots of undergrowth along a horizontal plane and which finds special utility when employed for clearing land of undergrowth, shrubs, small trees, and the like. Land...

Undergrowth wild planting simulation method for rhizoma polygonati

Abstract: The invention discloses an undergrowth wild planting simulation method for rhizoma polygonati The undergrowth wild planting simulation method for rhizoma polygonati comprises the following steps: (1) selection of a forest land: selecting the forest land with evergreen broad-leaf forest and mossy dwarf forest on the ground as a planting field; (2) land preparation: after deep tillage, base fertilizer application, re-digging, comminution, and leveling, making an annular soil surface layer by layer in the forest of the planting field from the slope top to the slope base of the planting field; (3) cultivation of rhizoma polygonati: ditching the made annular soil surface and planting rhizoma polygonati seedlings; (4) field management: performing weeding and ridging, irrigation and drainage, light transmittance adjustment, topdressing, topping and overwinter management; and (6) harvesting: after planting for five years or more, harvesting the rootstock of rhizoma polygonati The undergrowth wild planting simulation method for rhizoma polygonati creates a favorable environment for the growth of rhizoma polygonati, and not only guarantees that rhizoma polygonati in the whole forest is uniform and favorable in growth vigor, but also greatly improves the survival rate, pests and diseases are reduced, residues of both pesticides and fertilizers are avoided, and the quality of rhizoma polygonati is effectively guaranteed

Comparison of tree growth and undergrowth development in aerially seeded and planted Pinus tabulaeformis forests

Abstract: Direct seeding is a less expensive practice than planting and has the potential to become a viable alternative to transplanting for afforestation and regeneration purposes. As an effective and a less costly regeneration method, aerial seeding has been applied with several tree species. As early as 1956, Chinese people engaged in aerial seeding and stands with a total of 2.97×107 hm2 have been developed up to 2004. Our study tested whether the growth of planted Chinese pine (Pinus tabulaeformis Carr.) seedlings and its undergrowth development in northwest aspects differ from that of aerially sown seedlings on the northern and northwestern aspects of slopes. In 2007, we collected data such as height, diameter at breast height (DBH), clear bole height and canopy widths of trees, abundance, coverage, and frequency of shrubs and herbs from 21-year-old planted Chinese pine stands on a northwestern aspect (PNW), aerially sown stands in a northwest aspect (ANW) and aerially sown stands in a northern aspect (AN). Results showed that the relation of crown area and mean DBH was best fitted by a double inverse model for the ANW and AN forests and by a quadratic model for the PNW forest. There was no difference in the growth between ANW and AN forests, while growth was significantly higher in the PNW forest than in the ANW and AN forests. That was consistent with the Sorenson diversity indices in the shrub and herb layers, indicating that there was a large number of the same species in both aerially seeded stands, although their locations were different. Both the number of species in the undergrowth and the Shannon-Wiener index in the shrub layer were higher in the PNW stands than in the ANW and AN stands. Dominant families for all three stands were Rosaceae and Compositae in the shrub and herb layer, respectively. The dominant species for all three stands was Spiraea pubescens in the shrub layer, while the dominant species was different from each other in the three stands. The discrepancy in diversity and composition of species in the herb layer show that herbs are sensitive to shrubs in the three forests. High mortality and skewed diameter distributions reflect severe competition and too high a density in the aerially seeded forests. Thus, aerial seeding is a viable and effective regeneration technique, but management practices, such as thinning, should be applied to these forests.