Department of Botanical & Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab, India.
Post Graduate Department of Zoology, Khalsa College, Amritsar, Punjab, India.
BMC Ecol. 2020 May 7;20(1):27. doi: 10.1186/s12898-020-00296-5.
Earthworm communities are generally very sensitive to physico-chemical properties of the soil in different agro-ecosystem i.e. cultivated or non-cultivated which directly or indirectly influence the earthworm survival. The difference in physico-chemical properties of soil at different sites contributed to the formation of population patches for earthworm species. Understanding the physico-chemical properties of soil at a particular site could facilitate the prediction of earthworm species at that site. The objective of the present study was to investigate the diversity, abundance, and distribution of earthworms in cultivated and non-cultivated agroecosystems and their physico-chemical properties affecting the earthworm diversity and abundance.
Total 10 species of earthworms i.e. Amynthas alexandri, Amynthas morrisi, Eutyphoeus incommodus, Eutyphoeus waltoni, Metaphire birmanica, Metaphire houlleti, Metaphire posthuma, Octochaetona beatrix, Perionyx excavatus, and Polypheretima elongata, were reported. Out of all the reported species, Metaphire posthuma was found to be the most abundant earthworm species in both cultivated and non-cultivated agroecosystems with the occurrence at 56.81% sites. The Shannon-Wiener index (H), Margalef species richness index (D) and Pielou species evenness (E) was ranged from 0 to 0.86, 0 to 0.64 and 0.78 to 1 respectively. The principal component analysis resulted in four principal components i.e. PC1, PC2, PC3 and PC4 which contributing variance (%) of 22.96, 19.37, 14.23 and 10.10 respectively. The principal component analysis also showed that physico-chemical parameters of soil such as EC, pH, TDS, texture, OC, moisture, etc. play a critical role in earthworm distribution.
The conventional farming system has a negative effect on the earthworm diversity in the soil while the physico-chemical properties of soil also have a determinant effect on the same. Earthworms abundance in the present study have significant direct relation with soil properties at a particular site and vice versa. The diversity indices also change due to the conventional farming system which directly affects the earthworm abundance.
蚯蚓群落通常对不同农业生态系统中的理化性质非常敏感，即耕种或未耕种，这些性质直接或间接影响蚯蚓的生存。不同地点土壤理化性质的差异促成了蚯蚓物种的种群斑块的形成。了解特定地点的土壤理化性质可以促进对该地点蚯蚓物种的预测。本研究的目的是调查耕种和未耕种农业生态系统中蚯蚓的多样性、丰度和分布，以及影响蚯蚓多样性和丰度的理化性质。
共报告了 10 种蚯蚓，即亚历山大蚯蚓（Amynthas alexandri）、莫里斯蚯蚓（Amynthas morrisi）、不常见沟胸蚓（Eutyphoeus incommodus）、沃顿沟胸蚓（Eutyphoeus waltoni）、缅甸巨蚓（Metaphire birmanica）、胡氏巨蚓（Metaphire houlleti）、后孔蚯蚓（Metaphire posthuma）、斑彩副唇蚓（Octochaetona beatrix）、环毛蚓（Perionyx excavatus）和长尾蚓（Polypheretima elongata）。在所报告的所有物种中，后孔蚯蚓是在耕种和未耕种农业生态系统中最丰富的蚯蚓物种，在 56.81%的地点出现。香农-威纳指数（H）、马加利夫物种丰富度指数（D）和皮埃罗物种均匀度指数（E）的范围分别为 0 至 0.86、0 至 0.64 和 0.78 至 1。主成分分析产生了四个主成分，即 PC1、PC2、PC3 和 PC4，它们分别贡献了 22.96%、19.37%、14.23%和 10.10%的方差。主成分分析还表明，土壤的理化参数，如 EC、pH、TDS、质地、OC、水分等，对蚯蚓的分布起着关键作用。
传统耕作系统对土壤中蚯蚓的多样性有负面影响，而土壤的理化性质也有决定性的影响。本研究中蚯蚓的丰度与特定地点的土壤性质有显著的直接关系，反之亦然。多样性指数也因传统耕作系统而发生变化，这直接影响蚯蚓的丰度。
