scholarly journals The significance of the seed bank as a potential for the reestablishment of arable-land vegetation in a marginal cultivated landscape

Web Ecology ◽  
2001 ◽  
Vol 2 (1) ◽  
pp. 83-87 ◽  
Author(s):  
R. Waldhardt ◽  
K. Fuhr-Bossdorf ◽  
A. Otte

Abstract. As part of the German Research Foundation (DFG) project “Land Use Concepts for Marginal Regions”, since 1997 we have made analyses of the seed bank of 22 cultivated allotments, as well as of 15 meadow/pasture and 16 fallow allotments on former arable land of the Lahn-Dill Highlands, a marginal cultivated landscape in Hesse, Germany. One aim of this study is to determine according to which dynamic laws the seed bank of arable-land weeds is depleted after cultivation is abandoned. Depending on the intensity of the arable land use, the seed banks of rankers and cambisols that are presently still cultivated contain up to 1 004 800 seeds of arable-land species capable of germination m−3. Soils that were last cultivated less than ten years ago have much lower seed densities, while the seed bank of arable-land species is largely exhausted after only ca. 20 yr. This points to an exponential depletion of the seed bank of arable-land species and their abundance over time. On the basis of the present results, <20 yr remain in the Lahn-Dill Highlands for the reestablishment of characteristic arable-land vegetation from the seed bank.

Land ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 41
Author(s):  
Yi Lou ◽  
Guanyi Yin ◽  
Yue Xin ◽  
Shuai Xie ◽  
Guanghao Li ◽  
...  

In the rapid process of urbanization in China, arable land resources are faced with dual challenges in terms of quantity and quality. Starting with the change in the coupling coordination relationship between the input and output on arable land, this study applies an evaluation model of the degree of coupling coordination between the input and output (D_CCIO) on arable land and deeply analyzes the recessive transition mechanism and internal differences in arable land use modes in 31 provinces on mainland China. The results show that the total amount and the amount per unit area of the input and output on arable land in China have presented different spatio-temporal trends, along with the mismatched movement of the spatial barycenter. Although the D_CCIO on arable land increases slowly as a whole, 31 provinces show different recessive transition mechanisms of arable land use, which is hidden in the internal changes in the input–output structure. The results of this study highlight the different recessive transition patterns of arable land use in different provinces of China, which points to the outlook for higher technical input, optimized planting structure, and the coordination of human-land relationships.


2021 ◽  
Author(s):  
William R. Shoemaker ◽  
Evgeniya Polezhaeva ◽  
Kenzie B. Givens ◽  
Jay T. Lennon

Fluctuations in the availability of resources constrains the growth and reproduction of individuals, which in turn effects the evolution of their respective populations. Many organisms are able to respond to fluctuations by entering a reversible state of reduced metabolic activity, a phenomenon known as dormancy. This pool of dormant individuals (i.e., a seed bank) does not reproduce and is expected to act as an evolutionary buffer, though it is difficult to observe this effect directly over an extended evolutionary timescale. Through genetic manipulation, we analyze the molecular evolutionary dynamics of Bacillus subtilis populations in the presence and absence of a seed bank over 700 days. We find that the ability to enter a dormant state increases the accumulation of genetic diversity over time and alters the trajectory of mutations, findings that are recapitulated using simulations based on a simple mathematical model. While the ability to form a seed bank does not alter the degree of negative selection, we find that it consistently alters the direction of molecular evolution across genes. Together, these results show that the ability to form a seed bank affects the direction and rate of molecular evolution over an extended evolutionary timescale.


2019 ◽  
Author(s):  
Ajishnu Roy ◽  
Kousik Pramanick

AbstractAgriculture, along with industry and household sector are three major sectors of human consumption. Agriculture has proved to be a major contributor to exceeding planetary boundaries. Here, we have explored the impact of agriculture in the Earth system processes, through eight dimensions of planetary boundaries or safe operating spaces: climate change (10.73%), freshwater use (91.56%), arable land use (37.27%), nitrogen use (95.77%), phosphorus use (87.28%), ecological footprint (19.42%), atmospheric pollution (2.52% - 38.08%) and novel entities. In this work, we have also shown role of agriculture to the socio-economic development dimensions: gender equality, employment and economic growth. We have shown that the safe operating limits for agriculture are going to decline by almost 55% (climate change), 300% (freshwater use), 50-55% (arable land use), 180% (nitrogen use), 265% (phosphorus use) and 20% (ecological footprint) in 2050, if the most inefficient way of consumption is chosen and continued. To alleviate the role of agriculture in transgressing planetary boundaries, it is indispensable to comprehend how many roles of agriculture is playing and where which target should be set to framework the national agricultural policies in coherence with attaining sustainable development goals of UN by 2030.


GCB Bioenergy ◽  
2018 ◽  
Vol 11 (3) ◽  
pp. 466-482 ◽  
Author(s):  
Nicola Di Virgilio ◽  
Osvaldo Facini ◽  
Andrea Nocentini ◽  
Marianna Nardino ◽  
Federica Rossi ◽  
...  

2009 ◽  
Vol 19 (2) ◽  
pp. 103-114 ◽  
Author(s):  
J. Plue ◽  
J.-L. Dupouey ◽  
K. Verheyen ◽  
M. Hermy

AbstractRecently, forest seed banks were proven to not only reflect former (decades-old) but also ancient (centuries-old) land use. Yet, as land-use intensity determines the magnitude of seed-bank changes in recent forests, this study aims to identify whether an ancient land-use gradient would also be reflected in the seed bank. On a forested 1600-year-old archaeological site, five different land-use intensities were mapped and sampled. Apart from seed density, species richness and composition, functional seed-bank types, defined by nine seed-bank-related plant traits, were related to the land-use intensity gradient. The land-use gradient from gardens to undisturbed sites was still clearly reflected in the soil seed bank. Six emergent functional seed-bank types, characterized by specific plant traits, changed significantly in abundance, parallel to the land-use gradient. In particular, dispersal agent (and related traits) proved an important explanatory trait of present (functional) seed-bank patterns. Poor dispersers (large and heavy seeds) were not found in the intensively used areas, contrary to animal-dispersed species. Wind-dispersers may have been inhibited in the extension of their distribution by recruitment bottlenecks (low seed production) and/or competitive exclusion. Additionally, the agricultural land-use probably introduced ruderal species into the seed bank of the most intensively used areas, yielding a simultaneous increase in vegetation–seed-bank dissimilarity with land-use intensity, eliminating present vegetation as a driver behind the differences over the seed-bank gradient. We conclude by arguing how coppice-with-standards management possibly maintained the seed-bank gradient.


2020 ◽  
Vol 222 ◽  
pp. 03009
Author(s):  
A.V. Bezgodov ◽  
K.A. Galimov ◽  
V.F. Akhmetkhanov

The object of the research is to study the influence of the method of growing mown and grain-forage varieties of spring vetch in mixed crops with spring rapeseed on the seed yield and crop structure. Indicators that characterize productivity, intensity of arable land use, competitiveness and aggressiveness of crops are considered. Sowing spring vetch with a seeding rate of 1.3, 0.8, 0.6 and 0.4 million germinating seeds per hectare mixed with rapeseed leads to the formation of a grain crop that significantly exceeds the yield for single-species vetch sowing. Evaluation of Land Equivalent Ratio (LER) shows that when using vetch-rapeseed crops, the productivity of 1 ha of arable land increases from 1.38 to 1.98 times, while both the influence of varietal specificity and the seeding rate of the legume component is manifested. The efficiency of arable land use increases due to the interaction of both crops and increasing their competitiveness in the agrocenosis. In the conditions of the Middle Urals, high efficiency of vetch cultivation in mixed crops with rapeseed was revealed, and the influence of changes in the seeding rate on the yield of spring vetch seeds was established.


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